gal/elm 796 OF n15 I M 5w‘ Q c} n COLLEGE ' T exas Range Plants ' oimnous to L ivestoc/e New Mexico 03%“ “f AQEQEIEQFE and Mecbanifi Aft! TEXAS AGRICULTURAL EXPERIMENT STATIUN - - - TEXAS AGRICULTURAL EXTENSIBN SERVICE College Station, Texas CONTENTS Page INTRODUCTION ............................................. -- 3 THE PROBLEM .............................................. -. 3 ACKNOWLEDGMENTS ................................. _- 3 PART 1. PLANTS MOST COMMONLY TOXIC TO LIVESTOCK Acacia berlandieri, Guajillo ...................... -- 4 Aesculus spp., Buckeye ______________________________ __ 5 Agave lecheguilla, Lechuguilla .................. -. 6 Aplopappzas heterophyllus, Rayless goldenrod .................................... -. 7 Asclepias latifolia, Broad-leafed milkweed ____________________________ -- 8 Asclepias subverticillata, Ho-rsetail milkweed ________________________________ __ 9 Asclepias verticillata, Whorled milkWeed.- 11 Astragalus a/rgillophilus, Yellow-flowered loco ________________________________ __ 11 Astragalus earlei, Earle loco ...................... __ 12 Astragalus emoryanus, Peavine ................ _- 13 Astragalus mollissimus, Woolly loco .......... -- 14 Astragalus wootoni, Garbancillo ................ .. 15 Baileya multiradiata, Desert baileya ........ .- 16 Dry/maria pachyphylla, Thickleaf drymary 17 Eupatoriunz r-ugosum, White snakeroot .... .- 18 Euphorbia spp. Spurges ______________________________ __ 19 Flourewzsia cernua, Blackbrush .................. ._ 19 Gutierrezia microcephala, Threadleaf broomweed ____________________________ __ 2O Helenium spp., Sneezeweed ...................... -. 21 Hymenowys odorata, Bitterweed .............. -- 21 Karwinskia humboldtiana, Coyotillo ........ .. 23 Nolina texana, Sacahuista .......................... -_ 24 Notholaena sinuata var. cochisensis, Jimmy fern .............................................. __ 25 Owytropis lambertii, Lambert loco ____________ __ 26 Peganum ha-rmala, African rue ................ -- 26 Prunus spp. Wild plum ................................ .- 27 Psilostrophe gnaphalodes, Paperflower .... -- 28 Psilostrophe tagetinae, Paperflower .......... -. 28 Quercus spp., Oaks ...................................... ‘>1 29 Senecio longilobus, Threadleaf groundsel.--. 30 Senecio flddellii, Riddell groundsel .......... .. 31 Sophora secundiflora, Mescal bean ......... 32 Xanthium spp., Cocklebur ......................... -- 33 Zygadenus nuttallii, Death camas ______________ _- 34 PART II. PLANTS LESS COMMONLY PART 111. PLANTS ONLY OCCASIONA’ REFERENCES ...................................... .; ...... I INDEX ............................................................. .; TOXIC TO LIVESTOCK Aloysia lycioides, Whitebrush .................... -- _ Amaranthus spp., Careless Weed .............. .. f Apocynum cannabinum, Dogbane, Indian hemp ............................ .. Cicuta curt-issii, Water hemlock ................ .. _i Cicuta maculata, Spotted hemlock ............ Claviceps spp., Ergot .................................. .. , Coniu-m maculatum, Poison hemlock .......... -. I Conyza coulteri, Conyza .............................. .. 1 Delphinium, carolinianum, Larkspur ........ .. i Delphiniztwl, virescens, Larkspur ................ .. Hypericum perforatum, St. J ohnwort ...... .- Kallstroemia hirsutissima, Hairy caltrop ....................................... M elilotus alba, White sweetclover .............. Melilotus officinalis, b} Yellow sweetclover .................................. Phyllanthus abnormis, I § Abnormal leafflower ............................... -_ Pteridium aquilinum var. pseudocaudatum, Bracken fern ............................................ .. Sow-twellia flaveria, Sartwellia .................. -§ Sesbania drumvnondii, Sesbane .................. -.l Solanum spp., Nightshades ........................ ..< Sophom sericea, Silky sophora .................. .. Sorghum halepense, J ohnsongrass ............ Sorghum vulgare, Sorghums ...................... TOXIC TO LIVESTOCK Baccharis pteronoides, Baccharis .............. Cephalanthus occidental/is, Buttonbush .... Corydalis aurea, Golden corydalis ............... .3 Datura metaloides, J imsonweed ................ .i._; Datura stramomum, J imsonweed f. .......... Descurania pinnata, Tansy mustard ........ Lantana spp., Lantana .......................... -- Melia azedarach, China berry .............. .. Neriuvn oleander, Oleander .................. -- Nicotiana glauca, Tree tobacco ............ .- Phytolacca americana, Pokeweed .............. Psoralea ten-uiflora, Scurf pea ................. Ricinus conzm-unis, Castor bean .................. .: i3 gt? TY-NINE PLANTS ARE LISTED IN THIS BULLETIN. I includes the 34 most hazardous plants on range; Part II includes 22 plants that have toxicity, are not abundant or are not fre- ently grazed, and are less hazardous; and Part includes 13 plants recorded as toxic but usually i» considered hazardous. Since common names ze not always accepted generally and more than fe may be in common use, all plants are entered phabetically by genera in the text and by com- ;- n and scientific names in the index. Poisoned animals should be treated as soon 4' the condition is recognized. Treatment of _ imals that have eaten poisonous plants is based )1 four principles: destruction of poisonous sub- “fwnce within the alimentary tract, prevention of orption into the blood stream, promotion of cretion and evacuation and symptomatic treat- nt to assist the animal in returning to a normal te of health. Poisoned animals should be oved from accessible poisonous plants and ivided with feed, water and shelter. Some 'mals need hand feeding and watering. Specific ” idotes are available for some poisons but others uire symptomatic treatments such as laxatives, 'mulants and good nursing. " --. . . - -‘ THE PROBLEM p The problem of livestock losses from poison- f = plants is as old as the range livestock industry. i varies within localities from year to year and ' becoming more important as the quality of the estock and the value of the land increase. _ Most of the plants poisonous to livestock on xas range areas are native plants. They are azed when desirable forage is scarce, and when ‘lting and watering facilities are inadequate. Overgrazing and periodical drouths are gely responsible for the decrease of the more irable forage species and the consequent in- ase of the toxic and other less desirable species brush and weeds. Deferred and rotation zing, moderate stocking, adequate livestock tribution and water conservation measures are nge management practices that may be followed a improve native pastures and reduce weeds. echanical and chemical weed control, used in njunction with range management practices, - practical in many situations. Mechanical atments, such as mowing, chopping, grubbing espectively, professor, Department of Range and For- try, College Station, Texas; veterinarian, Animal Dis- it: Laboratory, Marfa, Texas; range specialist and xtension range specialist, Department of Range and orestry, College Station, Texas. T exas Range Plant; P0 zlronous to Livertoc/e OMER E. SPERRY, J. W. DOLLAHITE, JUDD MORROW and GARLYN O. HOFFMAN* or even hand pulling, reduce the current Weed population and destroy the seed source. When poisonous plants are abundant, chemical control usually is more economical than manual or me- chanical control. Experimental and practical applications of herbicides, especially 2,4-D, M.C.P. and 2,4,5-T, justify recommendations for the control of several species. ' ACKNOWLEDGMENTS Information on poisonous plants in this bulletin was brought together from the literature and from over 20 years of study and contact with field workers and ranchmen on Texas range areas. Research on poisonous range plants was started in 1947 in the Department of Range and Forestry of the Texas Agricultural Experiment Station, and has been supported principally by Federal-grant funds made available to the Station by the 1946 amendment to the Bankhead-J ones Act. Data on the distribution maps were compiled from herbarium specimens, collectors’ logs, collec- tions, field notes of the senior author and research assistants and literature records. Actual specimen collections are shown onthe maps by a solid dot, and field records by an X. An exception is found in Figure 5, in which Aesculus arguta is repre- sented by solid dots and other species of Aescnlus are indicated by solid squares. An occasional record on the maps outside of the general distribu- tion area usually indicates an uncommon occur- rence. Herbaria consulted were those of the University of Texas, Southern Methodist Univer- sity and the Tracy Herbarium of the A&M College of Texas. Figures 6, 27, 43, 67 and 69, taken by the senior author, are from Plants of the Big Bend National Paris by McDougall and Sperry (1951). All other pictures were taken by the senior author in connection with the Texas Agricultural Experi- ment Station research program. The overall organization and conduct of the studies reported were the responsibility of the principal investigator. Other persons concerned worked on certain aspects of the problem. J. W. Dollahite assisted in compiling information on ani- mal symptoms and toxicity. Judd Morrow worked with the distribution of plants and made a gener- alized survey of literature. Garlyn O. Hoffman assisted in field work on control of certain plants and reviewed literature concerning animal toxi- city and symptoms. The encouragement and cooperation of mem- bers of the Department of Range and Forestry contributed materially to the bulletin. Vernon A. 3 Young assisted with the early organization of the project, read the original manuscript and has of- fered many constructive suggestions. Frank W. A Gould read the manuscript and assisted with plant descriptions. Robert A. Darrow contributed the data on the chemical control of oaks. Apprecia- tion is extended the following research workers for assistance as noted: H. B. Parks, former cura- -_ tor of the Tracy Herbarium, plant distribution ---- notes; V. Glen Stickley, research assistant, white ~- snakeroot research and plant distribution data; W. . . V. Anthony, assistant range specialist, Animal . a- ---- -- . Disease Laboratory, field work; Floyd W. Pond, ._ """"" "" research assistant, buckeye research; and Frank ” P r """ " oooo ~- ' ' ~ . > x . B. Stroud, research assistant, reference citations. "" " __ " f. _ d4 ...... .. l. _ . . . 1*‘ "l-"~'7"'~»-‘>'"'.fll.’7' " i ‘ The assistance of others who contributed in T" any way, as well as all literature information, a T'- ---ai---~-. included or cited, is gratefully acknowledged. ll: 1. PLANTS MOST COMMONLY TOXIC TO LIVESTOCK The following plants usually are considered the most hazardous on Texas ranges. All parts ACACIA BERLANDIERI of the plant are poisonous at all times for some Figure 2. Guajillo, Acacia berlandieri. species, while others may be toxic only in certain GUAJILLO ~ . growth stages and then only specific parts of the DESCRIPTION, A Shrub in the legume fa l; A Dlallt- (Leguminosae) with few or no prickles, . . . . pinnate leaves and flowers in globose heads. mafia?“‘iiaztruiedba? a; flagteneg pods W long . ' wi e an ave somew a 1c ene margins, y iause of tbs potelfitlal dangerFm? betzaus? they ure 1. This shrub is closely related to catcl, ave Qause muc range anlma polsomng at Acacia greggii, huisache, Acacia farncsiana, y some “ma mesquite, Prosopis spp. l DISTRIBUTION. Guajillo grows in great d ity in Texas, especially in the southern part of ? Edwards Plateau and in the central and north. parts of the Rio Grande Plain. It extends f Terrell county on the north to Webb county the south and eastward into Bee county. Scatte . plants and small patches of guajillo are found} areas adjacent to the Rio Grande Plain and Edwards Plateau and in the Trans-Pecos, cially in the Chisos Mountains, Figure 2. extends southward into Mexico. ANIMALS POISONED. Sheep and goats 5 poisoned by guajillo. POISONOUS NATURE. The toxic principle" not been determined. SYMPTOMS. Animals poisoned by gua appear bright and alert and have a good app but show varying degrees of muscular incoo nation. The rear legs are most commonly air. and a stilted gait, stumbling and falling andi; apparent lateral bending of the backs is evid" When the front legs are affected the animals j, . . as if placing the feet several inches above gr“! . A n I ; . A level. Symptoms are exaggerated to a p0llk€ l it " prostration when affected animals are A, _ move about. Goats show similar symptoms. Figure 1. Guajillo, Acacia berlandieri. significant gross pathological symptoms ‘ in determined through autopsies. The highest agree of affliction and the resultant incoordina- y of movement is reached after 6 to 9 months k exclusive guajillo diet. Cases are most frequent gollowing drouth. The affliction is referred to as Iggagillo wobbles” or “limberleg” (Price et al. . 3 . ' 5 MANAGEMENT AND CONTROL Guafiflozm a pvaluable browse plant, but when grazed to the clusion of other range forage for 6 to 9 months (“r longer, limberleg develops. Losses may be as pghigh as 5O percent during drouth years but are giegligible during seasons of considerable rainfall i (Price et al. 1953). Adjusted stocking rates and ‘supplemental feeding should be used to reduce gpotential poisoning. No experimental research gshas been done on the control of guajillo on the gauge. {Amscutus SPP. l BUCKEYE DESCRIPTION. Trees or shrubs with opposite lmately-compound leaves with 5 serrate leaflets. T? e flowers are polygamous in large erect panicles a tubular, 5-lobed calyx; 4 or 5 clawed and 1 equal petals; 6 to 8 stamens and a 3-celled ary. The fruit is a leathery capsule with 1 to 3 ‘rge glossy brown seed. Buckeyes are members i‘ the horse-chestnut family (Hippocastinaceae) , e'gures 3 and 4. The Mexican buckeye, Ungnadia ieciosa Endl., is a member of the soapberry ‘mily (Sapindaceae) and, as the name implies, not a true buckeye. Field inquiries and records fdicate that the Mexican buckeye is not poison- a s. 2 l Figure 3. Buckeye, Aesculus arguta. Figure 4. Buckeye, Aerculu: arguta. DISTRIBUTION. Four species of Aesculus have been recorded for Texas. These occur from East Texas to the eastern part of the Edwards Plateau. The “Hill Country” area, consisting of Real, Bandera, Kerr, Medina and Uvalde counties, is one of the greatest problem areas of livestock poisoning, Figure 5. The species recorded for this area are Aesculus arguta, A. discolor var. flavescens and var. mollis, and A. austrina. A. Figure 5. Buckeye, Aerculu; spp. discolor var. flavescens apparently is the more common form in East Texas. SITES OF INFESTATION. Buckeye usually is found on river bottoms and along the banks of streams. In the “Hill Country” the tree forms grow along streams while shrub forms extend into canyons and valley floors. ANIMALS POISONED. Leaves and young shoots of buckeye are browsed, often in large quantities, during spring and early summer. Cattle have browsed accessible growth quite heavily without being poisoned. Other animals, especially those new to the area, may be poisoned readily. Cattle frequently are poisoned and mules and pigs have been poisoned by experimental feeding. Although it has been reported that Indians roasted the seed and used them for food, children have been poi- soned by eating the large nut-like seeds. POISONOUS NATURE. At least seven species of Aesculus have been reported as poisonous when eaten by animals. Several glucosides have been isolated from species of buckeye (Muencher 1948), two of which are aesculin and fraxin. At least one species contains a narcotic alkaloid. SYMPTOMS. The nervous system of poisoned animals is affected and they show an incoordina- ted limb action. Weakness, vomiting, trembling, depression, paralysis and inflamed mucous mem- branes are recorded symptoms (Muencher 1948, Tehon et al. 1946). MANAGEMENT AND CONTROL. Chemical con- trol studies in 1953 and 1954 indicate that good kills on buckeye can be obtained by the basal application of 2 to 4 percent diesel oil solutions of the esters of M.C.P. or 2,4,5-T. The best kills Figure 6. Lechuguilla, Agave lec/aegzzilla. were obtained on stems under 6 inches in dia and notched around the bole near the grog The kill on larger trees was erratic but a def’; population reduction was obtained. Experim j foliage sprays of several herbicides and comb'_ tions at different levels did not give satisfac kills during the 1953 growing season. Since the heaviest grazing and conseq poisoning usually is on the early growth, should be kept out of heavily infested past; during the spring. Should poisoning occur s ulants should be administered as soon as pose and animals removed from the pasture. This M be followed by purgatives to remove the poiso material from the intestinal tract (Tehon at? 1946). »; AGAVE LECHEGUILLA w LECHUGUILLA DESCRIPTION. Each lechuguilla plant cons. of a crown bearing 20 to 30 thick, fleshy lea. 1 to 1% inches wide and from 12 to 24 inc long. The leaves are ascending with recu marginal prickles and terminate in a sharp spy The floweringscapes are 6 to 12 feet long y bear a terminal panicle with short branc, Figure 6. Numerous black flattened seed produced in a leathery, 3-cel1ed capsule. p plant requires 10 to 15 years to reach mat . then flowers, sets fruit and dies. Reprodu is by both seed and offsets around the base o 1 parent plant. The formation of offsets is st. lated by the browsing of the flowering s The century plant and maguey also are spy of Agave, which belongs to the Amaryllis fa (Amaryllidaceae) . c‘ DISTRIBUTION. Lechuguilla occurs in westward from the southern and western port ssss .- ------- 1- sun! ~~~~~~ I1 k vans t ... .... K ... 1.. - . - . -.-- __._..\ 1 ' “n” i ink" l l...» L, Q /' '( i / .\\ /Y.-.un/ nun» 1 . - -\ ..-- - . _,- _*-.-st~¥ : ..<.>.<;@-’-ere \ u \ ......-. ........i " ' . ‘Q / - m"; ......... Figure 7. Lechuguilla, Agave lec/aeguilla. Figure 8. Grazed lechuguilla. )f the Edwards Plateau across the Trans-Pecos ;o the Franklin Mountain at El Paso. The Ieaviest infestations are in the lOW rainfall areas )aralleling the Rio Grande and on the dry hills vf the Trans-Pecos, Figure 7. This plant extends westward into New Mexico and south into Mexico. SITES OF INFESTATION. Lechuguilla occurs :haracteristically on low limestone hills, dry val- leys and bordering canyons west of the Pecos river. ANIMALS POISONED. Sheep and goats are poisoned most frequently by lechuguilla, cattle less frequently and poisoning has not been re- ported in horses. a POISONOUS NATURE. Lechuguilla poisoning is due to the combined action of two substances, Elle a photodynamic agent, the other a saponin. € xternal symptoms of photosensitization are acti- yated by direct sunlight. Animals fed as little as l percent of their body weights of leaf material have developed “lechuguilla poisoning” which may jcause death. Serious losses under range condi- Qtions are due primarily to the saponin which bauses a liver damage and not to the photosensi- tization or swellhead (Mathews 1937). g SYMPTOMS. Jaundice, liver and kidney le- sions, at times edematous swellings of the face 5nd ears. The jaundice usually is so marked that t shows in every tissue of the animal’s body. All ternal organs become a golden yellow or orange Iolor. The skin under the wool turns yellowish, 2nd a yellow coloration, often evident in the white 1 the eyeball, may develop into a yellow secretion from the eyes. Animals show an early toxic condition, become listless and lose appetite. The ead may swell, weakness progress and the animal come emaciated. Finally, the animal may go to a coma and die. Since swelling of the ears head is evident the disease often is called swellhead” or “goat fever” (Mathews 1937 ). MANAGEMENT AND CONTROL. Lechuguilla isoning usually occurs from grazing the leaves ring the spring but may appear at any time during the year, Figure 8. Pastures exam- ined during outbreaks usually were extremely short of forage due to overgrazing or drouth or both. Reducing the number of animals on the range or removing them to pastures free of lechuguilla is recommended. Some animals will recover if placed in complete shade with feed and water. Many ranchmen have found supplemental feeding beneficial. Poisoning often shows up in ewes during the lambing season when they do not move about or come in for feed freely. Manage- ment- practices to maintain better range feed should be set up on pastures where poisoning occurs. APLIOPAPPUS HETEROPHYLLUS RAYLESS GOLDENROD, JIMMY WEED, ALKALI WEED DESCRIPTION. Rayless goldenrod is a member of the composite family (Compositae) but is not a true goldenrod. It is a bushy half shrub with numerous upright branches which arise from a perennial woody root crown. The branches, which range in height from 2 to» 4 feet, give rise to numerous yellow flower heads and then die back to the ground each year, Figure 9. Growth on Texas range areas starts in early spring and flowering begins in late summer. Reproduction is by seed following fall, winter and early spring rains. Figure 9. Rayless goldenrod, Aplopappu: laeterophyllzu. 7 Figure 10. Rayless goldenrod, Aplopappu: loeterop/ayllux. DISTRIBUTION. Rayless goldenrod is abun- dant in the Pecos River and Rio Grande valleys and frequent around water sites and irrigated areas of the Trans-Pecos, the Rio Grande Plain and the Plains country, Figure 10. SITES OF INEESTATIoN. Range areas along the Pecos River are largely associated with alkali sacaton (Sporobolus ai/roides), locally called salt grass. Rayless goldenrod often frequents drain- age areas, springs and irrigation canals. Large acreages along the upper Pecos have been infested through irrigation. ANIMALS POISONED. Cattle, horses and sheep may be poisoned by consuming the weed, and their young may be poisoned by their milk. Hu- mans may develop milk sickness or trembles by consuming milk from poisoned cows. POISONOUS NATURE. Tremetol, an alcohol, is present in both dry and green plant material and is thought to be the principle toxin. From 1 to 1.5 percent of the animal’s body weight of the plant fed over a period of 2 to 3 weeks has been found toxic. The poison of rayless goldenrod is cumulative and since there may be some elimi- nation, larger amounts would be required to be poisonous if taken over a longer period of time. Sometimes calves, colts and lambs sicken from the milk and die before the mother shows any symptoms. An average daily feeding of 1% pounds of the green plant per 100 pounds of animal, continued for a week, usually produces toxic symptoms or death (Couch 1929, 1930). SYMPTOMS. The most noticeable symptom of rayless goldenrod poisoning is trembling, espe- cially in the muscles about the nose, legs and shoulders. The trembling may be preceded by a period of depression and inactivity. The animal stands in a “humped-up” position and moves with a stiff gait. This stiffness and weakness is -. pronounced in the forelegs. The inactivity d ually increases and culminates in extended ness. In later stages, the animal lies down g of the time and eventually, in the more ser cases, is unable to rise. Most cases of poiso: result in constipation, vomiting, quickened p labored respiration and almost continuous d bling of urine. The abnormal respiration in sick anim short time before death is especially chara istic. Affected animals breathe with a prolo I inspiration being followed by a pause and th short and somewhat forcible expiration. In g later stages the animal may breathe in a set of gasps. Horses sweat profusely in early s y of poisoning. Autopsy findings are not especially ma I but are uniform. There usually is congestio the fourth stomach and intestines. The live generally pale, the bile thick, dark and viscid f the gall bladder distended. The brain and sp cord are congested in some cases (Marsh 192 . ? MANAGEMENT AND CONTROL. The ma ment and control of rayless goldenrod is esse in all areas of infestation. Infested areas 1 commonly fenced off to keep out animals du; the late fall and winter. Plants are grubb some localized areas. Late summer before flo ing apparently is the best time for grubbing. Herbicides appear to be an economical effective method of control in areas where. can be used. The esters of 2,4-D appli 2,000 and 4,000 ppm (0.2 and 0.4 percent water produced good kill the first season. growth and all plants on the experimental y" were dead at the end of the second year. plane applications of the esters of both 2,4-D e 2,4,5-T gave satisfactory first-year kills, *0 drouth for 2 years following experimental ~ prevented final evaluation of results. Eradica of rayless goldenrod and reseeding with desi range plants may be necessary to put much of p: infested rangeland back into production. Poisoned animals should be removed f infested pastures as soon as possible. The y. should be given milk from nonpoispned c Poisoned cows should be milked and the e. discarded. I and laxative feeds improve the animal’s cha of recovery. Drugs should be given by w‘, tube or byinjection as some animals have th paralysis (Tehon et al. 1946). '1 ASCLEPIAS LATIFOLIA BROAD-LEAFED MILKWEED DESCRIPTION. Broad-leafed milkweed perennial plant with stout simple stems a or more pairs of large thick leaves, Whichi not more than 1.5 times as long as wide. 5 flowers are greenish and give rise to 2 to 4 s r The use of purgatives, stimu A ids about 11/2 inches long, Figure 11. Of the 0 species of Asclepias recorded for Texas, broad- fed milkweed is noteworthy for its robust ture and leaf size, while all other Texas species A ve proportionally narrower leaves. The milk- weeds belong to the family Asclepiadaceae. DISTRIBUTION. Broad-leafed milkweed is fre- {iquent to abundant over much of the range country aof the Trans-Pecos, the Plains area and the Pcentral and western portion of the Edwards ifiPlateau, Figure 12. It is found from Nebraska Utah, south to Texas and west to Arizona. SITEs OF INFESTATION. Broad-leafed milk- Yweed is a common constituent of grasslands and is frequent along trails and roadsides. As with many weeds of low palatability, this species in- icreases on heavily grazed pastures. Extensive reas may become heavily infested with contin- ;uous overgrazing. POISONOUS NATURE. This plant is toxic to ttle, sheep and goats. Two steers after being bed 0.5 percent of the body weight and a sheep .5 percent (Mathews 1932) were poisoned by oung plants in the prebloom stage. Old fruited lants had no ill effects on sheep. In another ding experiment, leaves of green plants in the fwering stage were dried, ground, suspended in p water and given as a drench by means of a mach tube. Plant material in quantities of than 0.15 percent of the body weight of sheep j= d goats were lethal (Tunnicliff and Cory 1930). g Numerous cases of poisoning have been in- stigated for both sheep and cattlein which the y Qad-leafed milkweed was considered to have p. the causal agent. In all observed field cases, weed was taken in the very early growth stage jfore grass had started growth. Extensive losses have occurred as the result of moving both A eep and goats through infested areas; How- er, few range cases occur from eating mature nts under normal circumstances, and cattle M: eaten plants after frost without ill effects. \ \ SYMPTOMS. Poisoned animals show signs of igpdominal pain, have excessive salivation, labored y» Broad-leafed milkweed, Asclepias latifolia. gure 11. Figure 12. Broad-leafed milkweed, Asclepias latifolia. respiration and restlessness. Internal lesions are a congestion of the liver, spleen, kidneys and. pos- sibly the lungs. The liver and lungs may be swollen. Parts of the intestine may be congested and hemorrhagic. Poisoned animals apparently die quickly and without struggle (Tunnicliff and Cory 1930). MANAGEMENT AND CONTROL. Since most cases of poisoning usually occur on pastures in which broad-leafed milkweed is abundant, man- agement practices to improve the range condition is the best measure of prevention. When large- scale poisoning occurs, animals should be moved to clean pastures or penned and fed until both the milkweed and better forage have had an oppor- tunity to increase growth. No selective herbicide has been found which gives satisfactory control. The removal of plants along trails and in holding traps may prevent many losses, especially when hungry animals are being trailed. ASCLEPIAS SUBVERTICILLATA HORSETAIL MILKWEED DESCRIPTION. Horsetail milkweed is an erect-stemmed plant growing to a height of 5 feet from horizontal rootstocks. The narrow leaves are predominantly in whorls of 3, or oppo- site with margins rolled backwards. The umbel- late flowers are greenish white and give rise to seed pods 1 to 3 inches long, Figure 13. The seed have tufts of long silky hairs. This milk- weed was named A. verticillata var. subverticil- lata by Gray in 1876 and A. subverticillata by Vail in 1898. Woodson (1944) after an examina- tion of plants called Asclepias galioides concluded as follows: “The proper designation of A. gali- aides of the plains of the West-central United States and adjacent North-central Mexico, there- 9 Horsetail milkweed, Arclepias Jubverticillata. Figure 15. fore, is A. subverticillata. (A. Gray) Vail.” This name apparently is correct, even though A. galli- oides appears frequently in poisonous plant litera- ture. This species is similar to A. verticillata but differs from it by more extensive rootstock and a tendency to produce dwarfed, small-leaved axillary branches. I11 this latter respect it also resembles A. Jhsicularis Dcne. which, according to Woodson (1944), is frequently but incorrectly called A. mexicana. DISTRIBUTION. This plant is frequent in the Trans-Pecos, with some records from the western part of the Edwards Plateau, Figure 14. Most collections identified as A. galioides in herbaria from East Texas are probably A. verticillatol. From West Texas and Northern Mexico, the species ranges to Arizona, Colorado and Utah. SITES OF INFESTATION. Horsetail milkweed frequently is abundant in open pastures, along arroyos, draws, bar ditches and roadsides. Infre- quently it grows as scattered plants, usually in protection of low brushy growth in the grassland areas. POISONOUS NATURE. Several toxic compounds. some glucosidal in nature, have been reported for A. galioides, which according to earlier deter- minations is the same as our species. Cold alcohol 10 extracts, insoluble in water, contain the substa which is responsible for poisoning. Water solu toxins, probably glucosides, have caused narcoi in experimental animals without congestion of t central nervous system. Sheep are most susc tible, but horses and cattle also may be poison SYMPTOMS. Symptoms are loss of muscu control, staggering and falling, violent spas with salivation, trembling, dilation of pup' bloating, rapid and weak pulse, fever, labor respiration, respiratory paralysis and possi q ‘ death (Marsh et al. 1920). Congestion is fou in the walls of the fourth stomach, duodenu jejunum, ileum and cecum. The lungs and ki neys also are congested in some cases. l urinary bladder usually is empty. MANAGEMENT AND CONTROL. Milkweeds a distasteful to animals and are not commo . grazed unless hungry animals are confined milkweed-infested areas. Grubbing as a cont measure is not considered practical, due to t difficulty of removing all of the undergro rootstocks which give rise to new growth. C y rent experiments with selective herbicides h obtained top kill but the final evaluation of i tests cannot be made until the growing season- 1955. Where poisoning is a problem, small l0 V ized areas may be fenced off or the ani ‘_ it moved to pastures free of milkweed. The m a tenance of good palatable plants on the range I management practices is the best protection f p, poisoning. ' Animals poisoned by milkweed should '1 moved to shade, kept quiet and given plenty water. There is no specific treatment but -~{ tives and laxatives may be of value (Tehon et p. 1946). \\\\ no "r1Q-.’:."0Q Q s-‘v-am nu m." Z ‘Cb i=1 (“F A nuvouv 5&9“! n1 EZFEE . j S) Figure 14. Horsetail milkweed, Asclepia; Jubz/erticill; t0 igure 15. Whorled milkweed, Axclepia: verticillata. LEPIAS VERTICILLATA »> WHORLED MILKWEED DESCRIPTION. Whorled milkweed is a slender, plant which grows to a height of 3 feet i) a perennial rootstock. The narrow leaves he rolled margins and are arranged in whorls to 6 at each node. The umbellate flowers are nish white. The seed pods are from 2 to 3 es long and produce numerous flattened, red- -brown seed which bear long, silky hairs, I re 15. I DISTRIBUTION. Whorled milkweed is frequent ughout East Texas with occasional records a the Edwards Plateau and the Trans-Pecos, re 16. It ranges from Maine to Florida west yexas, and north to Colorado and North Dakota. SITES OF INFESTATION. This weed normally l j I s in dry and at times in poor soil, grasslands ' -marginal woodland areas. It may flourish l" i ditches, roadsides and to a degree in culti- .0 areas. .POIsoNoUs NATURE. Animals are not fre- itly poisoned by whorled milkweed in pastures ion the range, although experimental feeding shown that it is toxic (Glover et al. 1918) thus when abundant, a potential danger. i SYMPTOMS, MANAGEMENT AND CONTROL. The toms of this poisoning apparently are similar ose of horsetail milkweed, A. subverticillata, Figure 16. Whorled milkweed, Asclepia: verticillata. and the same management and control measures are recommended. ASTRAGALUS ARGILLOPHILUS YELLOW-FLOWERED LOCO DESCRIPTION. Yellow-flowered loco is a pe- rennial, much-branched legume with a woody root and with tips of fruiting branches ascending or erect. The entire plant is covered with matted woolly or silky hairs. Theleaves have long peti- oles and usually 11 or 12 pairs of leaflets. The flowers are yellowish white, rarely yellow or purplish, Figure 17. This species is related to woolly loco, A. mollissimus, and like it has glab- rous fruit; the most obvious differences between the two is in flower color and geographical range. DISTRIBUTION. Yellow-flowered loco appar- ently is restricted in its general range in Texas Figure 17. Yellow-flowered loco, Axtragalus argillopbilus. ll Figure 18. Yellow-flowered loco, Astragalus argillop/ailzls. to about eight counties with south Reagan county being the center of distribution, Figure 18. SITES OF INFESTATION. Yellow-flowered loco usually is found in clay soils in grasslands along draws and in depressions or lakebeds on the divides. POISONOUS NATURE, SYMPTOMS, MANAGE- MENT AND CONTROL. The toxicity, symptoms and control apparently are the same as for woolly and earle loco which follow. Cory (1930) reported authentic instances of cattle, horses and goats becoming “locoed” from eating the foliage of this species. Recent investigations also have been made of field cases of sheep poisoned by this plant. ASTRAGALUS EARLEI EARLE LOCO DESCRIPTION. Earle loco is a perennial leg- ume with a woody taproot and numerous decum- Figure 19. Earle loco, Artmgalu: earlei. l2 bent stems. The leaves, composed of an number of leaflets, are usually 3 to 5 inches, length but may be as much as 8 inches in len The purplish flowers are, racemes and the seed pods are about 1%; i T long and about 1/3 inch thick, Figure 19. Ast galus mollissimus, woolly loco, is very similar appearance and may, in some situations, be as on healthy plants. ciated with earle loco. There are numerous leguminous plants lated to earle loco growing in the same genei area; some are toxic but others may provide g i Peavine and garboncillo are the m The daleas, Dalea spf vetch, V icia exigua; deervetch, Anisolotus pub”; ulus; snoutbean, Rhynchosia, texana; and sevef other species of Astragalus are closely relatedii; forage. common tox1c specIes. the locos but are not poisonous to livestock. DISTRIBUTION. Earle loco is found chieflyi seven counties of the Big Bend area of Te Figure 20, and extends westward into New Me and south into Mexico. SITES OF INFESTATION. Earle loco is abundant in draws and flats, and in low rai it years is restricted to these areas. In good rai Q years it is found over much of the range areaf both igneous rock and limestone soils. Earle grows in good as well as overgrazed grass f and is commonly associated with buffalo g the grama grasses, cane and silver bluestems the lesser grasses such as the muhlys and sp of Tridens. POISONOUS NATURE. The toxic principle; earle loco is an alkaloid-like substance, which, been isolated and named locoine. Cases of fl poisoning usually occur from eating the plantlie its early growth stages. These stages, howe, are governed by the distribution of rainfall Earle loco, Artragalus edrlei. Figure 20. l l bundant growth may occur throughout the fall, éfwinter and spring. All classes of range livestock are susceptible to poisoning, with horses more susceptible than cattle, sheep or goats. The acute form of the disease “locoism” develops from eating large amounts of the loco although a chronic form of the disease may occur if small quantities are eaten over an extended period of time SYMPTOMS. Symptoms of locoism have been produced in cattle after they have consumed about 9O percent of their body Weight of the plant. However, it usually takes from 200 to 350 percent of the body Weight, eaten over a period of several months, to produce a fatal case of locoism in cattle, sheep or goats. About 30 percent of the body weight of the loco plant Will produce symp- toms in a horse and about 75 percent may be fatal (Mathews 1932). Animals poisoned from earle loco are ex- tremely nervous. Horses may rear and plunge. cattle shake their heads in a horizontal plane and sheep exhibit Weakness and depression (Mathews 1932). Mathews gives the most common symp- toms as slow staggering gait, rough coat, staring look, emaciation and muscle incoordination. Abortions were caused by feeding this plant to pregnant cows, the fetuses showing considerable maceration. MANAGEMENT AND CONTROL. Loco is most frequently consumed when ranges are short and dry. When palatable range forage is scarce, the use of supplemental feed tends to reduce the amount of loco consumed. Locoed animals should the removed from infested pastures and placed on §§good feed. Bitter tonics may be given by mouth ‘or added to the feed to stimulate the appetite. lWhen plenty of other forage is available most animals will not eat locoweeds, but when they have once been forced to eat them they fre- quently acquire the habit, eventually with fatal results. Animals raised where locoweeds are common usually will not eat them as readily as imported livestock. Ranchmen believe that a cow which is a confirmed loco eater will teach other cows to eat this plant. Susceptibility among animals of the same species is quite variable. The grubbing of plants to a depth of 2 or 3 inches below the surface is a practice on many ranches. This procedure may need to be repeated, as experiments show that a large percentage of the grubbed plants regrow during the season, especially with favorable rainfall. Excellent kills, 90 percent and better, have been obtained with 2,4-D in water spray solutions. One to 1%, pounds of the acid equivalent of the pester 2,4-D in 20 to 30 gallons of water per acre {have given the most consistent results. On small and spot treatments with wetting sprays, 0,2 percent (2,000 ppm) solutions are most satis- ,ctory. Plants sprayed from October through arch are killed, while April, May and June treatments produce topkill "only, with regrowth in late summer following rains. If a spraying program is inaugurated, some management pre- caution should be followed, as sprayed plants are as palatable and toxic as unsprayed plants. The removal of animals from a treated pasture until the treated loco has dried up prevents possible poisoning and gives the range vegetation a rest and growing period. This in itself should pay a good dividend in additional forage. ASTRAGALUS EMORYAN US PEAVINE, RED-STEMMED PEAVINE, EMORY LOCO DESCRIPTION. Peavine is an annual legume with a slender taproot and slender decumbent stems. The stems usually branch at the base and bear odd-pinnate leaves with acute-tipped leaflets. The glabrous seed pods are 2-celled and contain about a dozen seed. A. emoryanus is closely related to and often grows in association with other species of Astragalus such as loco, ground plum and garboncillo. One species called Nuttall peavine, A. nuttallianzts, frequently grows with A. emorydnus, and certain amounts have inad- vertently been included in the feeding experi- ments. It is probable that this species is also poisonous under the same conditions. A. emory- anus, Figure 21, was separated taxonomically from A. nuttdllianus by Rydberg in 1927. The obvious character of separation is: A. nuttalli- anus has truncate or emarginate leaflets; those of A. emoryanus are acute. DISTRIBUTION. Peavine has been recorded for every area in Texas except the Piney Woods of East Texas and the southern portion of the Rio Grande Plain. It is most abundant. and most troublesome in the Trans-Pecos area, Figure 22. It is distributed from Texas to California and Mexico. Nuttall peavine is also scattered“ over Texas with greatest abundance on the Ed- wards Plateau and Blackland Prairie. SITES OF INFESTATION. Peavine grows in short grass areas and on open ground, usually Figure 21. Peavine, Astragalu: emoryanux. 13 Figure 22. Peavine, Artragalu; emoryanus. assuming a prostrate habit. A single plant may cover only a few square inches or it may be 2 or 3 feet in diameter. When growing in moist, grassy areas of low vegetational density, it may develop a few-stemmed upright habit. POISONOUS NATURE. Feeding trials and range observations show that the greatest toxicity oc- curs from plants growing on limestone soils, primarily in Brewster, Presidio, and Culberson counties. Peavine also is toxic on red-sandy soils especially in the vicinity of the Llano River. Peavine is considered good forage in sections of the State where poisoning does not occur. The apparent mineral relationship to the toxicity has been studied by giving calcium gluconate, calcium chloride and monosodium phosphate preceding experimental feeding. Sheep given the mineral compounds were poisoned more readily than when peavine was fed alone. When the combination of soil conditions and abundant peavine growth pre- vails, cattle, sheep and goats may become poison- ed (Sperry et al. 1952). Peavine poisoning, in both cattle and goats, causes impairment of the motor nerve. In sheep the toxic principle has a specific action on the motor nerves as well as the respiratory center, or pneumogastric nerve. There is no evidence that grazing peavine becomes habit forming, as is the case with loco. The toxic principle in peavine is destroyed if it is dried for a period of 4 months (Mathews 1940b). SYMPTOMS. Under range conditions, the first evidence of toxic effects on cattle is the momentary collapse of the leg muscles when the animal attempts a sudden movement. This is overcome after a short hesitation, and the animal can move quite normally. As the disease pro- gresses, the incoordination of the hind legs l4 becomes more noticeable when the anima forced to run. Loss of weight and paralysis p; evident in later stages. A slow recovery usu is made when affected animals are put on ‘p and water with some shade (Mathews 1940b In addition to the incoordination of hind muscles, sheep develop a rasping noise due. labored respiration. This is intensified by tion and heat. Progressive loss of weight sporadic deaths are observed in sheep. ' Goats fed experimentally developed musc incoordination similar to cattle and sheep. Symptoms were p r o d u c e d by Math i (1940b) by feeding from 0.73 to 2.0 percenti the body weight of peavine, usually in a 2 v period. MANAGEMENT AND CONTROL. Since pea j normally is shortlived, the usual managem practice is to remove animals from pastures; which they are being poisoned for the dura ' of peavine growth. Peavine is not a probl every year, and pastures free from infestan’ may be held in reserve for use during prob i years. Close supervision of stock and the pl ment of poisoned animals on dry feed may av‘, some animal losses. Light stocking of pastures will limit peavine poisoning during “T years. Since peavine often grows earlier t. the grass and other nontoxic forbs, the preven of peavine poisoning during early spring is a problem which requires daily attention. A st-ock unaccustomed to grazing peavine should be placed in infested pastures, as acute poiso can result. More than 90 percent kill of peavine has 1f obtained by spraying with 0.2 percent (2, ppm) water solutions of a mixture of the of 2,4-D and 2,4,5-T. Since germination contiy throughout the growing season several treatml by this means may be required for control. i‘ Animals poisoned by peavine should penned with feed and water. Bitter tonics" be administered to stimulate the appetite. A ASTRAGALUS MOLLISSIMUS p WOOLLY LOCO, PURPLE LOCO DESCRIPTION. Woolly loco is a stout, dec. bent, much-branched, perennial legume. leaves have 19 to 29 ovate-oblong leaflets dent covered with hairs. The thick woody root rise to stem branches which tend to lie clo the ground, Figure 23. The flowers are pu I in color and the fruit pods are short, thick ' 2-celled. Woolly loco is distinguished from --;f loco by longer hairs on the fruit pods. DISTRIBUTION. Woolly loco is found prim 1 in the Plains area of Texas, although a* collections have been-recorded for the Big area, Figure 24. It is found as far nort South Dakota with eastern limits record, Central Nebraska and Kansas and in -.J Figure Z3. Woolly loco, Arimgalzzr nzollirsimur. Oklahoma. Its western limits approach Central Colorado and New Mexico. SITES OF INFESTATION. Woolly loco usually grows in localized patches, commonly in flooded iedraws in the Rolling Plains area, but is frequent- ely associated with buffalo and blue gama grass- land on the High Plains. POISONOUS NATURE. The toxic principle of oolly loco, as for earle loco, is locoine. The ffects are thought to be cumulative, with greatest sses among horses, especially in the northern art of its range. Numerous cases of cattle oisoning recently have been reported for the lains area of Texas. Woolly loco is considered ess palatable to cattle than to horses, and also "equires the consumption of a larger quantity by l ttle for acute poisoning. As in the case of earle co, sheep also are subject to the poisonous lement of woolly loco. \ ;--- q.....-\_.f.. U... / I a- 1'.'..'!...'.' .54 I I 1-‘: ' I .3... ..... L ' L. i I '...!.. L. .1. a. .2..- I x ' I I ll i _ i llal$fil i >' "" " .!..-.."_ I I ‘L l’ " -: l... :.= 1-. ‘- ' ’ I .... l,‘ . .'! ..... .. ..- midi-.-‘ t...- J 'Ll...I.L._I4._.j_ ‘wnlq/Qffllz. M‘ "fi \ ,4; ,\/ ---- v- Figure 24. Woolly loco, Astmgalus mollimimus. SYMPTOMS. The symptoms of woolly loco poisoning are similar to those recorded for earle loco. Internal symptoms are anemia, coagulated serum in the body cavity and inflamed stomach and intestines. External symptoms are much the same as those of earle loco. MANAGEMENT AND CONTROL. Since woolly and earle loco are closely related and similar in most respects, the management and control given for earle loco also can be applied to woolly loco. Early publications state that woolly loco can be destroyed by grubbing the plant to a depth of 2 or 3 inches below the ground. Seed of both species are longlived, thus new seedlings can be expected for several years even though the green plants are destroyed. ASTRAGALUS WOOTONI GARBANCILLO, RATTLE-WEED LOCO DESCRIPTION. Garbancillo is a much-branch- ed, annual legume with erect, hairy stems that vary from about 3 to 12 inches long, depending on habitat. The leaves are composed of 9 to 19 linear-oblo-ng leaflets, hairy beneath and smooth above. The pink or purplish to white flowers are in axillary racemes. The plant is conspicuous in fruiting because of the large, 1-celled, inflated pods, Figure 25. DISTRIBUTION. In Texas, garbancillo is re- stricted to the Trans-Pecos area, Figure 26. It is known as a common weed in the low rainfall areas of Southern New Mexico, Eastern Arizona and Northern Mexico. SITES OF INFESTATION. Garbancillo is most abundant in valley sites which accumulate runoff water from the surrounding hills and is common in bar ditches, along trails and around earthen tanks. It often occurs on rocky slopes and hills, but usually as reduced plants. It is frequently associated with dense growths of buffalo, curly mesquite and grama grasses. POISONOUS NATURE. Ranchmen have been of the opinion that garbancillo is much more toxic Figure 25. Garbancillo, Astragalus wootoni. 15 Figure 26. Garbancillo, AJtwzgalz/r zyooloni. than earle loco. Feeding experiments show that these two species are about equal in toxicity. Tests indicate that animals as a whole show a greater reluctance to eat A. zvootoni than A. earlei. The symptoms produced in animals fed garbancillo were identical with those of animals fed earle loco (Mathews 1932). Animals poisoned on the range frequently have access to garban- cillo, peavine and loco, making it difficult to determine which of the three are responsible. It is possible that some range cases are brought about by the consumption of more than one species. MANAGEMENT AND CONTROL. Since garban- cillo is an annual, grubbing and the removal of plant material around tanks, along roadways and in other localized hazard sites often is a profitable operation. If the plant is widely scattered or abundant over large areas and is being grazed to the extent of poisoning, the removal of animals from the pasture may be necessary. The plant dies out in early summer after fruiting. Spraying with a 0.4 percent water solution of the ester of 2,4-D has given fairly good kill, but the most consistent results have been obtained with a 50-50 mixture of the esters of 2,4-D and 2,4,5-T in a water solution. Spraying should be done while plants are young, certainly before fruiting and while plants are in a vigorous grow- ing condition. BAILE YA MULTIRADIATA DESERT BAILEYA DESCRIPTION. Desert baileya_is a low-grow- ing composite densely covered w1th short hairs which give it a woolly appearance. It has numer- ous, alternate, toothed leaves on numerous basal l6 Figure 27. Desert baileya, Baileya mz/ltiradiata. branches. The prominent’ yellow-flowered on elongated stems are present from spring late fall, Figure 27 . DISTRIBUTION. This species occurs frequ in the seven most western counties of T especially in the low rainfall areas of the Bend, Figure 28. From this area it exten Southern Utah, Nevada, Southern California south into Mexico. i SITES OF INFESTATION. Desert baileya is abundant on sandy and gravelly soils in semidesert grassland and shrub areas. It is conspicuous along roadsides and present extensive range areas. PoIsoNoUs NATURE. Desert baileya is in both the green and dry state. Although is a wide variation in the susceptibility of experimental feeding by Mathews (1983a) that 18 to 58 pounds of dry and 16 to 65 us; nu run vun u" ' ' " - . - - 1M » - . - - . . . . unn- vvvv .1 ---- u “- - - v > \ a 4 - - I ' ' " gun-v n“.- gun Figure 28. Desert baileya, Baileya multiradiata. qw- A when approached. f green plant material Were required to kill a o, eep. Goats were poisoned experimentally but Apparently do not eat the plant under range onditions. No losses were observed in cattle or orses, although both grazed the plant on the range. Losses up to 15 percent were reported 1n ilspheep (Mathews 1933a). ' SYMPTOMS. The first symptoms are a frothy- jgreen slobber, followed by extreme weakness, [rapid heart action and a trembling of the limbs. , The temperature, pulse and respiration remain normal unless animals are exercised. Extensive . hemorrhages on the heart and in the diaphram, congestion of the liver, spleen, kidney and mesen- teric blood vessels are observed in acute cases , (Mathews 1933a). On the range, animals affected by baileya either will stand with back arched and refuse to move, or when. lying down will refuse to get up They may follow the flock with a stiff gait, show marked weakness, trem- bling and loss of appetite. Affected animals taken to the corral and offered feed lie down most of { he time and refuse to eat for several days, but (eventually they begin to eat (Mathews 1933a). large percentage recover. p MANAGEMENT AND CONTROL. Since animals .0 not eat baileya except when range forage is packing, the provision of supplemental feed or ovement to better pastures usually will control p oisoning. Losses subside following rainfall suf- aicient to produce forage growth. Proper man- gement to maintain desirable range forage hould eliminate the poisoning problem. Experimental spraying with herbicides gave omplete kill when 2,4-D was applied in 0.4 ercent water solution at the rate of 30 gallons i: acre following rains. Spraying done while onditions were dry, even though plants appear igorous, was ineffective. ‘ {DRYMARIA PACHYPHYLLA THICKLEAF DRYMARY, INKWEED DESCRIPTION. Thickleaf drymary is a glab- rous, short-lived annual which grows close to the ground in a somewhat circular pattern up to 8 4 10 inches in diameter. The leaves are blunt- ointed and usually about as wide as long. Small lowers and small-seeded fruits are produced in the axils of the leaves, Figure 29. Thickleaf irymary is a member of the pink family (Cary- phyllaceae) and is related to and sometimes ionfused with the chickweeds, species of Stellaria . = nd Cerastium. p DISTRIBUTION. Drymary is frequent to abun- pant in the Trans-Pecos area of West Texas with 1 few records east of the Pecos River, Figure 30. t extends across New Mexico, Southeastern Ari- p1 and south into Mexico. SITES OF INFESTATION. Thickleaf drymary rows on sites with sparse vegetation, most com- Figure 29. Thickleaf drymary, Drymaria pac/oyp/oylla. monly on heavy clay soil and in low areas subject to flooding. POISONOUS NATURE. Cattle, sheep and goats are poisoned by both dry and green drymary plants. Most poisoning occurs on overgrazed ranges, and plants are most commonly grazed 1n the early part of the day while the plants are turgid. Feeding experiments have shown that 0.6 percent of the body weight will kill a sheep, 0.4 percent a cow and 0.9 percent a goat (Mathews 1940c). SYMPTOMS. Animals poisoned by drymary on the range usually die before the symptoms are recognized. This is in accord with the results of feeding experiments in which death occurred a short period after the first symptoms appeared. Figure 30. Thickleaf drymary, Drynzaria pac/ayp/aylla. 17 Diarrhea and loss of appetite are early symptoms but animals remain on their feet and stand with an arched back and tucked-up abdomen. The heart muscle is hemorrhagic, the wall of the gall bladder is edematous and thickened, and the liver and spleen show marked congestion and dark color. Hemorrhages and congestion also may appear in other organs (Mathews 1940C). MANAGEMENT AND CONTROL. Thickleaf dry- mary, being a short-lived annual, may produce more than one crop of plants during the growing As with most annual plants, drymary is more abundant and grazed more heavily on depleted ranges. Improvement of the range for- age is the only certain method of controlling the weed and eliminating the danger of livestock Most cases of poisoning occur on pastures with little forage during dry seasons but when light showers are sufficient to bring $633011. poisoning. on a weed crop. EUPATORIUM RUGOSUM WHITE SNAKEROOT, RICHWEED DESCRIPTION. White snakeroot is an erect, branching, herbaceous perennial composite from 1 to 4 feet tall. The slender, round stems may develop a purplish coloration, especially when growing in the open. Small clusters of white flower heads are produced at the ends of the The leaves are opposite, have 3 distinct veins and coarsely toothed mar- numerous branches. gins, Figure 31. There are approximately 30 species and va- r1et1es of Eupatorzum in Texas, some similar to f‘ Figure 31. White snakeroot, Eupatorium rugosum. 18 E. rugosum but, as far as known, not toxic. shey (1949) reported another species, E. wrigh as poisonous in the Rocky Mountain area. DISTRIBUTION. White snakeroot occurs p East Texas and as far west as the Chisos Mo tains but is most abundant and troublesome the Hill Country. Luxuriant growth is found . the north portions of Uvalde and Medina counti over most of Real and Bandera counties and p I portions of Kerr county, Figure 32. The gene Q distribution of white snakeroot is from easte North America westward to Minnesota and Te ' _ , (Couch 1933). ‘ * SITES OF INFESTATION. White snakeroot most frequent in wooded areas but may pers in open clearings. It frequents most hardw . areas in East Texas and is associated with juni’ and oak in the Hill Country. This plant u? I become abundant following timber clearing, I; cially in juniper areas. In the Hill Country, W I snakeroot is not confined to ravines and vall _ but extends up the slopes and occasionally 0 hilltops. p POISONOUS NATURE. Couch (1927) gives principle toxin of white snakeroot as an uni urated alcohol, tremetol. This alcohol is fou primarily in green tissue and decreases as plant dries. The poison is cumulative in eff; I, and is transmitted in the milk. Cattle, sheep other animals are reported to be susceptible the poison. _ SYMPTOMS. Symptoms of white snaker poisoning are trembling of muscles, especi after exercise; depression; weakness; inactivi s stiff movements with frequent stumbling falling; labored respiration; constipation; bl in feces and an odor of acetone in the (Couch 1933). Post-mortems reveal extens' . i, _e uu nun u... ----- 1- ----- u .1 ".1 ....; -. _-~4‘~-l.' _._.1__.'_._._4._ ' I u» Figure 32. White snakeroot, Eupaiorizzvn wugosum. egeneration of kidneys and liver (Wolf et al. 918). Humans are affected by the disease, and - acute cases usually show delirium and coma preceding death (Graham and Michael 1935). MANAGEMENT AND CONTROL. Ranchmen re- sjsport that poisoning usually occurs during late summer or early fall but may occur at any time igthe plant is consumed in quantity. Goats are f most commonly poisoned in Texas, and investi- ‘A gations show that animals introduced to the white n l snakeroot for the first time are readily poisoned. l Sheep have grazed white snakeroot without no- ¢ ticeable effects. When snakeroot is a problem, Q animals should not be pastured on infested areas, especially in late summer and fall. In localized ‘areas, plants may be pulled and burned, or iso- lated by fencing. A series of trial plots of white snakeroot were sprayed in Kerr county during 1952 with I formulations and combinations of 2,4-D and 2,4,5-T. A dry period during 1952 and drouth in 51953 prevented what may have been normal re- sults in this work. A good kill was obtained on the open dry sites however, with the amine formu- ilations showing slightly more promise than the Jesters of the herbicides. Poisoned animals should be treated the same for rayless goldenrod poisoning. UPHORBIA SPP. I SPURGES ., DESCRIPTION. The spurges are a large group f annual and perennial herbs and shrubs with _ilky, acrid juice. The leaves are simple and lternate, whorled or opposite on the stem. The onoecious flowers are in cup-shaped heads sur- ounded by 4 or 5-lobed involucres. A single "istilate flower is surrounded by staminate or fiile flowers and from it develops a 3-carpeled, seeded fruit. The spurges vary in habit from I at forms growing close to the ground to upright eafy or almost leafless plants. Closely related 511 the euphorbia family (Euphorbiaceae) are the Ecrotons (goatweed, doveweed) castor bean, bull nettle (Cnidosculus stimulosis), poinsettia, leaf- '_ ower and queen’s delight (Stillingia spp.). j DISTRIBUTION. Approximately 80 species and Yarieties of Euphorbia are listed by Cory and Parks (1.937) for Texas. Several additional spe- ies have been determined since the above publi- ftion. Some species are present in all sections of Texas, the most numerous of them in the southwest portion. At least eight species recorded .51’ Texas are known or suspected of being toxic '1 of the herbaceous species are weeds and i. Iairly abundant on overgrazed pastures and igdisturbed areas. At least one species, E. anti- philitica (candelilla) , is of economic importance I the Big Bend area because of the commercially aluable wax produced. POISONOUS NATURE. The acrid juice of a umber of species of this genus is reported to 1.. H ~ i, .' r- be toxic. A resinous substance, euphorbin, which is toxic or at least an irritant, has been extracted. Species other than those listed by various workers undoubtedly are potentially poisonous. One of the common properties of Euphorbia seed and other parts of the plants is the strong purgative effect. In a recent study, approximately 100 ounces each of E. prostrate» and E. marginata plants fed to cattle produced severe scours and emaciation (Hoffman 1954). The animals con- cerned were several months in getting over the effects. MANAGEMENT AND CONTROL. Since most of the spurges can be grazed to a limited degree without noticeable reaction, light infestations in pastures should not be a problem. When a heavy infestation is present, poisoning may be expected. As most pasture species of Euphorbia are annual weeds, management by mowing, possible reseed- ing with good forage plants and lighter stocking to improve desirable forage should be practiced. The bitter juice of the spurges apparently makes most species unpalatable and plants are grazed only accidentally when better forage is available. Intestinal astringents should be administered to poisoned animals to relieve the diarrhea. FLOURENSIA CERNUA BLACKBRUSH, TARBUSH DESCRIPTION. Blackbrush is a much-branch- ed, leafy shrub of the composite family. The leaves are alternate, entire, obovate or oblong. The rayless flowers are solitary in the leaf axils, forming a leafy inflorescence. The fruit is a 1-seeded achene. Blackbrush plants may not ex- ceed a foot in height in dry sites but attain a height and spread of 5 to 6 feet in more favorable situations, Figure 33. DISTRIBUTION. Blackbrush is frequent to abundant in the Trans-Pecos and in counties im- mediately east of the Pecos River. It extends across New Mexico into Arizona and southward into Mexico. Figure 33. Blackbrush, Flourenuia cernua. l9 SITEs OF INFEsTATIoN. This shrub grows on dry hills, plains and mesas, often on limestone areas. POISONOUS NATURE. Mathews (1944) dem- onstrated the toxicity of the ripe blackbrush fruit by experimental feeding to sheep and goats. A marked variation in the susceptibility of individ- uals was observed as well as a narrow margin between slightly toxic and lethal amounts. As little as 1 percent of the animal’s body weight of dry fruit eaten in 1 day will kill some animals. Range losses are usually the result of turning hungry animals into blackbrush-infested areas during the Winter. SYMPTOMS. The symptoms of poisoning from blackbrush according to Mathews (1944), are a listless attitude, arched back and a tucked-up appearance of theabdomen. Animals appear sick suddenly and many cases are fatal within .24 hours. Internally there is a marked congestion of the liver and kidneys. Ulceration of the fourth stomach and first foot of the small intestines is very common. In fatal cases there is usually necrosis of the wall of the fourth stomach W1th perforation of the ulcers in both the fourth stomach and first part of the small intestines. MANAGEMENT AND CONTROL. Interviews with ranchmen confirm the findings of Mathews (1944) that the green leaves are not toxic. Losses can be avoided by keeping hungry sheep off of blackbrush range short of other forage during the winter. Large areas of range in Pecos, Reagan and Upton counties were cut with roller brush cutters and the regrowth of blackbrush provided considerable forage. The pits made by the cutter helped hold water following rain, and judicious stocking helped improve grass growth and forage Figure 34. Threadleaf broomweed, Gutierrezia nzivrocep/Jala. 20 conditions in general. Unchopped blackbrus also browsed, especially the new growth. f THREADLEAF BROOMWEED, sNAKEwEED, f TURPENTINEWEED, SLINKWEED a DESCRIPTION. Threadleaf broomweed i many-branched, perennial, herbaceous compos The branches rebranch terminally to give (j to masses of yellow-flowered heads. The lea are alternate and filiform, Figure 34. Ei additional species of Gutierrezia, some ann f are recorded for Texas. Ranchmen consider of the perennial species as toxic and the follo statements will probably apply to other suspected as toxic. GUTIERREZIA MICROCEPHALA _ a! _ DISTRIBUTION. Threadleaf broomweed occ, in Central and West Texas. In general oneg more species of Gutierrezia are present in ev“ section of Texas but the perennial species more prevalent in Central and West Te Threadleaf broomweed extends south into Me * and west into Arizona, Utah and Nevada. SITEs OF INFESTATION. Threadleaf “j weed is frequent to abundant over much of ‘ range area of West Texas, especially the 1i Pecos. It increases with overgrazing and g.) luxuriantly along roadways and disturbed PoIsoNoUs NATURE. Numerous ranch believe that cattle are poisoned by grazing br { weed and that abnormal calf delivery or abo i resulted. Although fatal poisoning was obtai by feeding broomweed to sheep, goats and p (Mathews 1936), experimental evidence was? obtained to support the widespread belief in abortive properties. More recent experim feeding has been done, following outbreaks v condition in which calves were carried full t but died shortly before, during or shortly a birth. This was almost invariably followe retained placentas. Following feeding tr’; seven pregnant cows produced calves, two? which were normal, one dead, and four Two of the weak calves died before they we Y hours old. Five of the seven cows had reta" placentas. This work indicates that broom, poisoning produces some dead or weak calves is a cause of retained placentas. This experi j is being continued. * Li’. ¢ Q _._; 4- Q4 +4 _.L Q rm ¢A__; L;_Q- SYMPTOMS. The symptoms of bro0m poisoning based on the research of Mat (1936) are loss of appetite, listless atti, arched back, drooping head and, in severe pronounced hematuria 24 to 48 hours after; initial symptoms. Swollen kidneys, somet’ with hemorrhages in the cortex, and a yello mottled liver are internal symptoms. MANAGEMENT AND CONTROL. Early gr of new growth of threadleaf broomweed is mon on the dry ranges of the Trans-Pecos. D_ i dry years, the entire plant may be grazed a ground. Supplemental feeding when range f0’) Inn iii-mi scarce probably is the best preventive practice when it is necessary to graze cattle on broomweed i infested ranges. J Chemical control experiments of threadleaf l broomweed in 1952 and 1953 showed excellent kill with water solutions of the esters of 2,4,5-T and M.C.P. Kills of 90 percent or better were obtained with 0.2 percent solutions, while kills of 91 to 99 percent were obtained with 0.4 percent i solutions of 2,4-D, 2,4,5-T and M.C.P. The two t latter chemicals were consistent in giving the % highest kill ratios. l l -@_( _,-_-____.4 HELENIUM SPP. SN EEZEWEED DESCRIPTION. The most frequently encoun- tered species of Helenium in Central and East Texas is H. tenuifolium, bitter sneezeweed, also called bitterweed, eastern bitterweed and fineleaf sneezeweed. Bitter sneezeweed is a narrow- leafed, much-branched, annual composite with ‘rather showy flower heads of yellow ray flowers, Figure 35. H. "rmdiflorum, purplehead sneeze- lweed, recorded for East Texas, also is reported as toxic to livestock (Tehon et al. 1946). This is a lfperennial species with oval to linear leaf blades and many small purplish disk flowers. There are {about a dozen additional species of Helemum in 'the Texas flora which probably are not suffi- {ciently toxic to be problem plants. DISTRIBUTION. Bitter sneezeweed occurs from fCentral and East Texas across the Southeast FUnited States, and is occasionally found in the Northeast. Purplehead sneezeweed grows in the Piney Woods and Coastal Prairie areas of East Texas and extends east to Florida, with sporadic koccurrences as far north as Connecticut. 4 I SITES OF INFESTATION. Bitter sneezeweed is a common pasture and roadside weed throughout tits range. It grows in old fields, overgrazed pastures and waste areas. In Texas it usually loccurs on sandy or sandy loam soils. Purplehead ‘sneezeweed most commonly grows in moist areas of the prairies and woodlands. POISONOUS NATURE. Although the sneeze- lweeds have a bitter, sharp taste, some animals graze them in quantity, especially the young g-growth, when more palatable vegetation is scarce. addition to probable poisoning properties, the fisneezeweeds give a bitter taste to milk. This taste dairy products is often a serious problem, espe- éjicially in the case of bitter sneezeweed. The glu- {isocide dugaldin was determined as the toxic trinciple of orange sneezeweed, H. hoppesii, §{Marsh et at. 1921) and this or similar glucocides be present in other species. i ‘ SYMPTOMS. The symptoms of sneezeweed isoning are restlessness, rapid pulse, difficult Breathing, incoordination and sometimes photo- insitization. ~ Figure 55. Bitter sneezeweed, He/enzflnz te12ui_f0/iz1nz. MANAGEMENT AND CONTROL. Pasture man- agement to promote ample forage or to keep cattle out of pastures infested with sneezeweed should be practiced. Mowing before seed maturity greatly reduces the amount of bitter sneezeweed. Orange sneezeweed has been effectively controlled experimentally with 2,4-D at the rate of 4 pounds pure acid per acre (Doran 1951). Although experimental data are lacking, it may be assumed that reasonable control of bitter sneezeweed can be obtained with herbicides. HYMENOXYS ODORATA (ACTINEA ODORATA) BITTERWEED DESCRIPTION. Bitterweed is a member of the composite family. It is an annual, usually much- branched plant, that varies in height from a few inches to about 2 feet according to environmental conditions. Each of the ascending stem branches terminates in a yellow-flowered head. The flower heads are made up of many small flowers, and under normal growth conditions each head pro- duces from 50 to 75 seeds, Figure 36. Seedlings or older green plants may be found at almost any time of the year, but. most growth is from early spring to early or midsummer. If climatic con- ditions are favorable, growth may start as early as December. The plant has a bitter taste that apparently is strongest in mature plants and plants growing on dryer sites. Crushed or bruised leaves have an aromatic odor. 9' ZIYI Figure 56. Bitterweed, Hymenoxy; 0410mm. i Bitterweed is related to and in the same general growth area as the nonpoisonous stemmed bitterweed, Actinea scaposa; sneezeweeds, Hele- nium spp.; false damiana, Chrysactinia mexicana; limoncillo, Pectis spp.; and numerous other com- posites. Pingue, Actinea richardsonii, another poisonous plant of the same genus, causes heavy death loss of sheep on grazing areas of Colorado, Arizona and New Mexico. DISTRIBUTION. Bitterweed is found over most of Texas west of the 99th meridian. The heaviest infestations and the most severe death losses in Texas occur in about 12 counties in the eastern portion of the Edwards Plateau and the adjacent Trans-Pecos region, Figure 37. Bitterweed ranges from Central Texas to California and from Kansas south into Mexico. Bitterweed, Hymenoxy; odomta. Figure a7. tensive areas in overgrazed pastures and hea SrrEs OF INFESTATION. Among the most ct mon sites of bitterweed infestation are flo” sites, drainage areas, lakebeds, roadways , watering places. This weed also occurs on trampled and disturbed areas. ANIMALS POISONED. Although sheep poi ing is considered the big problem, some ca losses also have been attributed to bitterwl, poisoning. There have been numerous cases sheep poisoning by bitterweed, especially in i, Edwards Plateau region. Most poisoning winter and early spring before green range f0 is available. POISONOUS NATURE. Experimental feedi show that during drouth years the bitterw herbage is much more toxic than when gr under conditions of near normal rainfall (Bo ton et al. 1937). Marked variation in the quan. of bitterweed necessary to kill an animal is ra striking. This probably is due to a variatiof toxicity of the plant and a variation in su tibility of the individual animal. The mini lethal dose of green immature bitterweed f’ grown sheep is approximately 500 grams, or 1 pound, when eaten in as short a period of as 2 days (Hardy et al. 1931). ; SYMPTOMS. Loss of appetite, cessatio rumination, depression, indications of abdo l pain, bloating and green regurgitated mat about the mouth and nose are common symp», of bitterweed poisoning. Perhaps the most. stant post-mortem lesion observed is conge of the lungs. ‘The next most constant lesion served is the presence of hemorrhages on epicardium, which in a few cases have also observed of the endocardium and of the r’ pleura. The lymph nodes, especially the i maxillary and retropharyngeal, also very _ are markedly hemorrhagic or congested. F fourth stomach is perhaps the most sev affected of the entire intestinal tract, and i majority of cases the lesions here consist I congestion or even of hemorrhages. Simil‘ sions also may be found scattered throughout intestinal tract and are especially frequent ii duodenum. The other internal organs do always show marked changes (Hardy et al. 19 MANAGEMENT AND CONTROL. When bi, weed poisoning occurs, animals should be m to clean pastures or put on feed. There ' medical cure for severely poisoned animals. "‘ taken in small quantities, the weed undoub must be grazed for several days before the a becomes noticeably ill. The animal will within a few days if it is removed fro j bitterweed range at this time. When su recovered animal again is turned upon the b weed range, it will again require some day the animal to eat sufficient bitterweed to a sick. p ‘ 1 Reduced stockingrates, changes in the r of livestock and deferment of pastures from. .1 g during the growing season will improve the 7 ass cover of bitterweed infested ranges. This normal rainfall will greatly reduce, and in time practically eliminate, bitterweed from the Temporary relief and a reduction of bitter- cweed are obtained from hand pulling and destruc- tion of the weeds or by spraying with herbicides. Herbicidal control has been practiced with vary- mg degrees of success. The best kills have been obtained with the esters of 2,4-D. Water solutions ~at concentrations of 0.2 percent applied as wetting iosprays or a spray of 1 pound of the acid equivalent of 2,4-D in 25 to 50 gallons of water per ‘acre applied with power equipment has given good ikill. Mature bitterweed plants and those growing ' in dry habitats are difficult to kill with herbicides. K KARWINSKIA “HUMBOLDTIANA if coYoTILLo DESCRIPTION. » Coyotillo is a spineless shrub firs» the buckthorn family (Rhamnaceae) with iostly opposite, pinnately veined leaves. The all greenish flowers and brownish-black fruits Ere in the axils of the leaves. The fruit is an void-shaped drupe. The simple veins end in the toothed margins of the leaves and, being quite ’l - Figure 38. Coyotillo, Karwinxkia laumboldtia-na. \U >2 ' I *5 Figure 39. Coyotillo, Karu/inJ/éia loumboldtiana. distinct, are an aid in recognizing the plant in the field, Figures 38 and 39. DISTRIBUTION. Coyotillo occurs in the south- ern portions of the Edwards Plateau and Trans- Pecos and in the Rio Grande Plain of Texas, Figure 40. Marsh (1929) gives the general distribution as Southwest Texas and Mexico. SITEs OF INFESTATION. This shrub grows along arroyos, river canyons and on gravelly hills and ridges. POISONOUS NATURE. Marsh et al. (1928) reported on the experimental feeding of coyotillo. They found the seed and leaves toxic to most animals fed, including cattle, sheep, goats, guinea pigs, horses, swine and chickens. Poisoning may result from a single feeding but usually several days or weeks elapse after the initial feeding before symptoms appear. While as little as 0.2 _ Figure 40. Coyotille, Karwinskia laumboldtiana. 23 percent of the body weight of a sheep of ground coyotillo fruit may cause death, as much as 2O to 25 pounds of leaves are required to obtain this toxicity. Cattle appear less susceptible than sheep to the fruit toxicity but more so, in relation to body weight, in leaf toxicity. SYMPTOMS. Paralytic symptoms of the hind legs, called “limberleg” in sheep and cattle, are brought on by eating the fruits of coyotillo. The condition does not appear to be painful and the animal will linger for a long period if fed and watered. Leaves do not produce the paralytic condition but produce a chronic condition of unthriftiness, depression, weakness and even- tually death. Internally, small hemorrhages may be found on the heart and inflammation of the lining of the stomach and intestines. The swelling of the lymph glands is probably the most charac- teristic lesion (Marsh et al. 1928). MANAGEMENT AND CONTROL. There is no certain remedy for coyotillo poisoning and no recovery in severe cases; close observation during critical periods when the plant may be browsed is essential. Change of pastures or moving of animals to a noninfested pasture may prove bene- ficial. If poisoned animals are put on feed, purgatives and stimulants may be given. Some chemical control with 2,4,5-T has been reported, but more experimental work is needed before definite chemical control measures can be recommended. NOLINA TEXANA SACAHUISTA DESCRIPTION. Sacahuista is a perennial of the lily family (Liliaceae). The plants have a thick woody caudex which gives rise to numerous, clustered, long, narrow, fibrous leaves. The sev- eral flower stems bear numerous small white flowers in somewhat elongated clusters. The fruit is a dry, 3-parted capsule. The flower stalks usually are not apparent until the plant is in full bloom, Figure 41. Figure 41. Sacahuista, N olina texamz. 24 Figure 42. Sacahuista, N olina texand. DISTRIBUTION. Sacahuista occurs in Til from Bell and Travis counties on the east to western boundaries of the State. It is abun on the Edwards Plateau and the Trans-P i but less frequent in the Plains area, Figure It extends into Southeast Arizona and North, Mexico. SITES OF INFESTATION. slopes. POISONOUS NATURE. The flower buds, ers and fruits of sacahuista contain a liver-ki toxin, which with fresh green forage beco photodynamic, causing photosensitization. SYMPTOMS. The phytodynamic sympto sacahuista poisoning are similar in cattle, s The symptoms given by Math (1940a) are a loss of appetite, generalized j _. and goats. dice, laggard action and progressive debilita- Affected animals have a yellow nasal discha“ A purplish band, probably a phytodynamicf; sponse, generally is found around the top off hoof above the coronary band. Itching, a gen" photodynamic symptom, is frequent as" an reaction to sunlight and apparently becomes; intense as the disease progresses. Most poisi animals die within a week, although some ani will recover if placed in shade with feed water. 1T Internal symptoms are generalized jaun yellow-brown liver and dark greenish-bro i greenish-black swollen kidneys. MANAGEMENT AND CONTROL. Sacah blooms during the winter and early spring. during the early flowering period that ani especially sheep, consume large quantities. mals find the early flower stalks before-theyl’; Sacahuista us grows in open grassland on rolling hills I iobvious and Mathews (1940) has shown that amounts greater than 1 percent of the body lweight for a period of about a week may be a lethal. Therefore, close attention should be given ‘l’ to this plant during the early blooming period. Unless the sacahuista stand is dense, most y operators do not wish to eradicate or control. k, When range grasses are dry, the green leaves of j sacahuista are browsed and, although the plant ’~‘ is very fibrous, some nutrition is obtained. Green- i nosed animals, especially cattle, can be observed j readily and these appear to be healthier than l. those that apparently do not browse the fibrous i; plants. g To avert poisoning, animals should be re- . moved from the sacahuista-infested pastures fduring the danger period. Recent field cases indicate that lambs are more susceptible to saca- ¥ huista poisoning than older sheep and cattle. l NOTHOLAENA SINUATA var. COCHISENSIS JIMMY FERN DESCRIPTION. Jimmy fern is an evergreen, erect fern with simple, pinnate leaves. The numerous leaflets are scaly beneath and smooth above. The leaves are from a short, chaffy, woody rootstock (stem), Figure 43. Growing in r dry habitats, this fern is of the “resurrection” f type, in that the leaflets roll and become quite dry when moisture is lacking, unroll and appear f, green and fresh following rain. DISTRIBUTION. In Texas this fern is found in the southwest part of the Edwards Plateau, iand the Trans-Pecos, and there are a few records gfrom canyons in the Plains area, Figure 44. It iiiiextends into New Mexico and Arizona and south into Mexico. SITES OF INFESTATION. Jimmy fern grows on rocky slopes and crevices and is often closely ,_ associated with some of the grasses characteristic i of dry habitats. i“ "x ¥$§§¥aar:fix5~a.»a aa,“ Figure 43. jimmy fern, N otbolaerza Jinuata var. c/Jixenrix. Figure 44. Jimmy fern, Ndt/aolaena sin/mid var. coc/oirenrir. ‘POISONOUS NATURE AND SYMPTOMS. The toxic nature of jimmy fern was determined by Mathews (1942) first by feeding the animals, then by walking them, about 48 hours after feed- ing. After exercise, sheep have an arched back, a tilted movement of the hind legs and usually increased respiration. In attempting to keep up with the flock, affected animals may stop and tremble violently, rest 15 to 30 minutes and then proceed. Successive attacks may appear. Death occurs suddenly either while animals are being handled or moving along the trail. Nonfatal cases require 5 to 19 days for recovery. The disease occurs in sheep, goats and cattle and in this order of severity. In a parallel feeding experiment, Mathews (1945) did not find the species (N. sinuata) toxic. Both the green and dry plants contain the poisonous principle. The trembling reaction, called “jimmies” develops about 48 hours after animals are fed as much as 0.5 percent of their body weight of the fern and exercised. It takes from 10 to 6O minutes of walking to develop syiliiptoms. The toxic principle is secreted in the mi . MANAGEMENT AND CONTROL. Since jimmy fern usually grows in rough, rocky areas, control of the plant would be difficult. Most fatalities occur in winter, thus close observations with suf- ficient forage or supplemental feed should be sup- plied to animals on infested pastures during this period. Under severe conditions, animals should be moved from pastures in which jimmy fern is abundant Under range conditions it is importantto leave sheep strictly alone during the danger period, since excitement or exercise will bring 25 on the symptoms and often death. Ample water- ing places should be provided in pastures where jimmy fern grows so that animals will not have to travel far to water. OXYTROPIS LAMBERTII LAMBERT LOCO, CRAZYWEED, POINT LOCO DESCRIPTION. Lambert loco is a perennial legume with basal pinnate leaves from the crown of the deep taproot. The leaves have 11 or more linear leaflets which often are covered with appressed silky hairs. The flowers are violet to bluish purple, Figure 45. Flower color ranging from white or yellowish white is reported for the species in some of the mountain states. The genus Oxytropis may be distinguished from Astragalus (i.e. earle loco, woolly loco, etc.) by a peculiar point or appendage on the keel of the flower, and by the absence of stems or branches above the crown of the plant other than the scape- like flower stalks. DISTRIBUTION. Lambert loco occurs on open grassland of North-central Texas and the Plains area. It extends westward to Eastern Arizona and northward across the Rocky Mountain States into Canada. SITES OF INFESTATION. This loco usually grows on well-drained sandy or gravelly soil and frequently on rocky knolls. Po1soNoUs NATURE. All parts of Lambert loco are toxic and the poison is cumulative. The effects of the poison may not show up until several weeks after the plants are grazed. Horses, cattle, sheep and especially lambs are reported as susceptible to the plant’s toxicity. Loss of flesh, irregular gait, erratic actions and incoordination are common symptoms, similar to those of other locos. Marsh and Clawson (1929) have given detailed information on the locos. MANAGEMENT AND CONTROL. The removal of “loco eaters” from an infested range is always good practice. Eating of this plant is somewhat l \QNI" Figure 45. Lambert loco, Oxytropis lambertii. 26 habit forming in animals and they may aga graze the plant if given the opportunity. Gru bing several inches below the surface gives fa, control. Bohmont (1952) reports that Lambert l can be controlled with either the ester or amid forms of 2,4-D at the rate of 1 pound to the ac Since the ester forms of 2,4-D have given t, best control in our experimental work with ea loco (see page 13), the spraying of Lambe, loco with herbicides should give good control. PEGANUM HARMALA AFRI-CAN RUE DESCRIPTION. African rue is a much-branc ed perennial herb of the Caltrop family (Zy' phyllaceae). The alternate, dissected, succule leaves are glabrous and divided into narrf § segments. The flowers have 5 white petals a. the fruit is a 2,3 or 4-celled many-seeded capsul Figure 46. DISTRIBUTION. Records show that Afri = rue has been collected in Texas in six or sev counties of the Trans-Pecos and Edwards Plat), . Figure 47. Recent collections in Presidio coui . are not shown on the distribution map. It is a recorded for New Mexico and Arizona. Afri rue was introduced near Deming, New Mexi * (Cory 1949) and apparently has spread i Texas and Arizona from this introduction. is a native of North Africa and Asiatic deserts...’ SITES OF INFESTATION. The heaviest inf tation of African rue in Texas appears to be the Pecos Air Field near Pecos and has spr along the highway south for 25 to 30 miles, a north and west to a lesser extent. Plan g introduced in Edwards county have been era cated (Cory 1949). POISONOUS NATURE. African rue has -.* proved poisonous by experimental feeding (BlT and Parker 1936, Moran et al. 1940, Math) 1940-1941) . Alkaloids have been extracted i‘ Figure 46. Atrican rue, Peganum laarmala. _ e pr mf.~.1_,d‘,_ -/ -{- ll county have been attributed to this plant considered hazard sites for livestock grazing in the area concerned. POISONOUS NATURE. Several species of Prunus are considered cyanogenic plants and may develop hydrocyanic (prussic) acid and when browsed they may cause livestock losses. The acid develops under certain conditions by a chem- ical reaction between a glucocide and an enzyme contained in the plant. Hydrocyanic acid is pro- duced in the animal’s stomach or rumen after mastication. Numerous factors and conditions such as bruising, wilting, withering or drying of leaves appear to contribute to the glucocide-en- zyme formation, but it is seldom known whether conditions favorable for the formation of these constituents are present. Caution always should be observed when Prunus occurs in pastures. SYMPTOMS. Symptoms of hydrocyanic-acid poisoning as given by Couch (1940) are rapid reaction of the animal to the poison, usually dying in a few minutes. The animal may, how- ever, live for several hours after symptoms de- Figure 47. African rue, Peganum harmala. velop. Brief stimulation is followed by depres- si_on_ and paralysis; colic may appear, and stupor, the plerye The Seed are meet toxic, and the difficult breathing and frequent convulsions may leaves and stems less so. Cattle losses in Reeves result Death 1S Caused by TBSPIPatOTY Paralysls- (Mathews 1940) Guinea pigs Sheep and cattle MANAGEMENT AND CONTROL. Medical care flihave been killed by feedings of 1 percent of their ‘known losses from African rue are few, its poten- SRUNUS SPP. frequently is difficult to administer early enough body weights. SYMPTOMS. Loss of appetite, listlessness, (weakness of hind legs and a buckling of fetlock ejoints are symptoms of African rue poisoning. ; dema and some hemorrhage beneath the serous coat of the small intestine also occur. MANAGEMENT AND CONTROL. Even though itial toxicity should be recognized and the plants pulled or grubbed out when found. The foliage gpparently is not palatable as it is grazed only by hungry animals. WILD PLUM, CHERRY, CHOKECHERRY DESCRIPTION. Plants of the genus Prunus re shrubs or small trees with alternate or fas- icled, simple leaves. The flowers are in elong- ted or somewhat flat-top clusters or solitary I the axils of the leaves, Figure 48. The fruit 1 a fleshy, 1-seeded drupe. There are numerous ecies in this genus with a wide distribution. bout 25 species and varieties, some escapes from eltivation, have been recorded for Texas. The Prunus usually is included in the rose mily (Rosaceae). e DISTRIBUTION AND SITES OF INFESTATION. veral species of Prunus are present in every tion of Texas, some growing in open areas, T ers as undergrowth in wooded sites. Some i the shrubby species form motts in fields and gturgs 0r alQ-ng fence rows, These are usually Figure 48. Chokecherry, Prunus Jerotina var. Jerotina. 27 to save animals severely poisoned by hydrocyanic acid. A solution of sodium nitrite and sodium thiosulfate is a specific antidote for cyanide poisoning. It may be given intravenously or intraperitoneally. If given intravenously the animals usually recover in a very short time. The same drugs are available in tablet form that can be given by mouth, but the action is so slow that the animal usually dies before they are absorbed. Mechanical and chemical eradication are suggested if followed by removal of root sprouts which may develop abundantly. From the prac- tical viewpoint, the motts, which are the biggest problem, can be fenced off and in turn will serve as excellent sources of wildlife cover and food. PSILOSTROPHE GNAPHALODES AND PSILOSTROPHE TAGETINAE PSILOSTROPHE, PAPERFLOWER DESCRIPTION. The psilostrophes are peren- nial composites with erect, woolly, tufted stems branching from the base. The leaves are alter- nate, entire or lobed. These plants have numer- ous, small heads of yellow flowers. P. tagetinae differs from P. gnaphalodes in having narrower ray flowers and being less woolly. It also has smooth achenes, the latter has woolly achenes. In general, the habit and growth of the two species are similar, Figure 49. DISTRIBUTION. P. tagetinae grows primarily in the Trans-Pecos and extends into the Plains area, Figure 50. From Texas it extends south into Mexico, west into Arizona and northwest into Colorado. P. gnaphalodes is frequent in the Trans-Pecos and Rio Grande Plain, Figure 51, and extends south into Mexico. POISONOUS NATURE. Range observations in- dicate that the two species of Psilostrophe are quite palatable to sheep. Limited feeding tests indicated that P. tagetinae is slightly more toxic than P. gnaphalodes (Mathews 1934). Dry and Figure 49. Psilostrophe or Paperflower, PJiZOJIVOPhE grmpbalodes. 23 Figure 50. Psilostrophe or Paperflower, Psiloxtropbe tagetinae. young plants are more toxic than mature bloom-f" ing plants, although losses of sheep have been-i recorded when the plants are in full bloom. Bot, species are suspected of being toxic to cattl‘ Field cases appear to confirm this, but experif mental feeding of cattle has not ascertained i ’ actual poisonous relation. Extensive sheep loss in the Trans-Pecos have been caused by th_ grazing of Psilostrophe. 1 SYMPTOMS Symptoms of psilostrophe poi-i soning are stumbling, sluggishness, coughing and~ Figure 51. Psilostrophe or Paperflower, PJilwt-rop grzap/oalodes. _ i Si. , x vomiting. The vomitus is generally liquid and greenish (Mathews 1934). MANAGEMENT AND CONTROL. Psilostrophe is grazed in winter as well as in spring and summer. Mathews (1934) suggested systematic pasture rotation. Since sheep have t0 eat the plant for approximately 2 weeks before they show symptoms, and since they will recover if removed from the plant when symptoms first appear, pasture rotation works effectively. When poi- soned sheep are observed they should be removed from the range and placed on feed. They usually recover. Psilostrophe is grazed occasionally by cattle. Top kill has been obtained by experimental spraying with 2,4-D, however the underground parts were not completely killed as new growth was prevalent the following year. More experi- mental work is needed before chemical methods of control can be recommended. QUERCUS SPP. OAKS, SHINNERY, SHIN OAK DESCRIPTION. The oaks are shrubs or trees with alternate, entire, toothed or lobed, persistent or deciduous leaves. The staminate flowers are catkins; the pistillate flowers are solitary or iclustered. The fruit is a 1-seeded nut (acorn), partly enclosed in a saucer-shaped involucre. There are about 1,000 species of oaks in the Northern Hemisphere, exclusive of the Arctic; isabout 400 in the new world, centering in Central iMexico and extending northward to Canada and olumbia. About 40 species with numerous varieties and hybrids have been recognized for a exas (Muller 1951). The oaks family is a agaceae. DISTRIBUTION. Species of oak are present throughout Texas and range in habitat from dry § o wet situations, and from sandy to limestone and lay soils. . POISONOUS NATURE. The toxicity of oaks sually has been attributed to the tannic-acid g ontent of the leaves. The work of Marsh (1919) ndicates that cattle can withstand considerable mounts of tannic acid without harm and that he toxicity probably is due to other substances. ome scientists think that it is not the leaves or uds, but the bark of the young tender limbs that s poisonous. Cattle eat considerable amounts of hese small limbs when browsing on buds and eaves. Oak leaves are browsed and are fair forage n combination with other forage. If eaten exclu- lively, they may cause serious trouble at any ason. Most cases of poisoning occur in the rly spring when other feed is scarce and the ks are in bud, or when the leaves are young gnd tender. . Cattle show a marked preference for oak in rtain stages of growth. They like the swelling Figure 52. Shin oak, Quercm loavardii. buds and minute leaves and flowers but do not care for three-quarter to fully grown leaves. After the leaves become older, animals like them again (Marsh 1919). a SYMPTOMS. The first symptom, according to Marsh (1919), is constipation, with infrequent passing of small lumpy feces. This is followed by the passing of a stringy mucus with the feces which may be bloody. As the disease progresses, the mucus forms a greater portion of the defe- cated material and a diarrheal condition may exist. In the early stages of oak or bud poisoning the animal looks gaunt, has a rough coat, dry nose and a peculiar standing and walking attitude. The animal shows discomfort, depression and pain, probably from an inflamed condition of the alimentary canal. The animal grows weaker and may die within a few days to 2 weeks or even longer. Afflicted animals may lose their appetite, but they usually appear thirsty. It is common to find dead animals a short distance from water, having reached the last stages of poisoning after drinking. Loss of weight and slow, often incom- plete, recovery are noted in animals that survive poisoning. Other symptoms given by Marsh (1919) include: normal respiration, weak pulse becoming rapid just before death, severe gastroenteritis, inflamed and often swollen mucosa of the small intestine and abomasum and usually areas and patches of congestion in the caecum and rectum. Poisoned animals are anemic and accumu- lations of serum usually are found beneath the skin and the walls of the fourth stomach and intestines. MANAGEMENT AND CONTROL. Bud poisoning is caused by several species but more commonly by the low-growing forms or shin oaks. In some species, one habitat xvill produce tree forms, while the shinnery type of the same species is found in other situations. The shin oak most commonly causing poisoning is Quercus havardii, Figure 52; the most common tree form is Spanish oak, Q. texcma. Most operators recognize the state of 29 growth which causes poisoning and keep cattle out of the pastures for the time concerned. Most heavy losses occur when animals are turned into the pastures before the oak has passed the early leaf-flower stage. On many ranges, oak browse is an important part of the forage; it is highly important to recognize the toxic period and move livestock accordingly. There is no specific treat- ment for oak-bud poisoning. Symptomatic treat- ment usually is employed but results have been discouraging. * Sand shinnery oak may be effectively con- trolled with low volatile esters of 2,4-D at 1 pound per acre in 5 gallons of diesel oil or in an emulsion consisting of 1 gallon of diesel oil and 4 gallons of water applied in aerial treatments. Applications should be made for 3 consecutive years to obtain maximum control. Shin oak on limestone soils does not respond readily to aerial spray application of herbicides. Tree types of shin oak may be deadened by trunk base appli- cations of 1 pound of 2,4,5-T as low-volatile ester in 6 gallons of diesel fuel. Post and blackjack oaks may be controlled by the basal bark application of 2,4,5-T esters and by aerial spray application of 2 pounds per acre of 2,4,5-T esters in 4 to 5 gallons of spray. Retreatment with 1 or more pounds of 2,4,5-T the following year may be necessary to obtain maximum control. SENECIO LONGILOBUS THREADLEAF GROUNDSEL, WOOLLY GROUNDSEL DESCRIPTION. Threadleaf groundsel is a many-stemmed, perennial composite. It is ever- green on Texas ranges. The leaves usually are pinnately divided into 3 to 7 segments and may be hairy or nearly smooth. The stems are her- baceous except at the base and also have variable hairiness. Yellow flowers are produced through- out mild winters and the blooms are abundant following summer rains, Figure 53. Senecio is one of the largest genera of flower- ing plants. Plants of this genus are known as Figure 53. Threadleaf groundsel, Senecio longilobzu. 3U senecios, groundsels and butterweeds. Seve species of Senecio, other than threadleaf grou sel, also are known or suspected of being poiso a ous. In addition to S. riddellii, Riddell groundi a of West Texas, S. glabellus, butterweed, has i strongly suspected of causing trouble in North , Texas. Some species of Senecio are consider fair to good forage. l DISTRIBUTION. Threadleaf groundsel is frequent to abundant in grassland areas 0v most of the Western half of Texas, Figure 54. i; ranges south into Mexico, north into Nebras‘ and Wyoming and west into Arizona. SITES OF INFESTATION. Threadleaf ground is a native forb or half-shrub, usually growing association with grama and buffalograss. extends into short-grass desert scrub areas an increases with disturbance and overgrazing. POISONOUS NATURE. The poisonous princip of threadleaf groundsel is probably an alkalo (Manske 1931). Most workers agree that t leaves are more toxic than the stems and t p young leaves are more toxic than older gro n . It is browsed throughout the year and often a high degree when the ranges are dry or duri snow and ice storms. On Texas ranges, cattle t most commonly poisoned, although walking ease of horses, caused by a species of Sane? is reported (Van Es et al. 1929). l SYMPTOMS. Symptoms of threadleaf grou sel usually are delayed several weeks or e months after grazing. The principal sympto‘ are continuous walking with a slight stagg rough coat, scaly nose and a fixed, staring exp 1 sion. The direction of travel may be inde minate, and the animal often runs into fencl other animals or objects. Death frequently ‘ Figure 54. Threadleaf groundsel, Senecio longilobuf due to exhaustion from animals becoming entan- led in fences or brush. The most prominent ternal lesions are the distention of the gall fladderyfirm, congested and finely mottled ap- trance of the liver and edema of the visceral syritoneum. Ranchmen report abortion and ab- figfzlormal calf delivery in cattle which feed on iSenecio. ~ MANAGEMENT AND CONTROL. If “Senecio eaters” can be detected, a change of pastures or removal from the herd is a good precaution. 4;?‘ Supplemental feed when pastures are in poor i‘, condition and eradication by chemical spraying Tare good management practices. By the time symptoms of Senecio poisoning appear, the liver l, damage is so extensive that treatment is useless. Q *1» g Several years of experimental control re- search indicate that threadleaf groundsel can be rkilled with 0.4 to 0.6 percent water solutions of fthe ester forms of 2,4-D or a combination of the esters of 2,4-D and 2,4,5-T. On large-scale ap- fplications, from 1 to 1% pounds of the acid equiv- in 30 to 40 gallons of water per acre or as Wetting spray have given satisfactory results. he best kill is obtained following rains during e growing season. Treated plants go through n abnormal growth period and may not die com- efpletely until early in the second season after treat- ent. ENECIO RIDDELLII I RIDDELL GROUNDSEL _ DESCRIPTION. Riddell groundsel is a herba- Laus perennial. Several stems grow from a goody base, which produce lateral branches, at 3- - st terminally. The leaves are pinnatifid, green without hairs, like the stems and flowers. a ellow flowers are produced in somewhat flattish nflorescences during late summer and early fall, ell A Figure 55. Riddell groundsel, Senecio riddellii. Figure 55. The major differences between this species and threadleaf groundsel are the bright green color, less diffuse branching and the die- back to the ground after frost. DISTRIBUTION. Riddell groundsel is frequent to abundant in the western half of Texas, with records from four to five counties along the Gulf Coast south of the Guadalupe River, Figure 56. This species ranges from West Texas and New Mexico, north into Colorado, Wyoming and Ne- braska. SITES OF INFESTATION. This species occurs in grasslands, foothills and sandhill areas. It is often abundant in disturbed and overgrazed areas, gravelly washes, flooded areas and along roads and trails. POISONOUS NATURE. Mathews (1933) found that S. longilobus and S. "riddellii were about equal in toxicity and that the disease was practically identical with that caused by other species of Senecio. SYMPTOMS. The symptoms of S. riddellii poisoning are the same as for S. longilobus, ac- cording to Mathews (1933). MANAGEMENT AND CONTROL. Mathews (1933) was of the opinion that S. longilobus was eaten more extensively than S. riddellii which grows in the same general area. More recent observations in the Trans-Pecos area indicate that Riddell groundsel is grazed heavily in the spring when new growth starts and again in the fall, especially after the first frost. Not all ani- mals graze Riddell groundsel and some animals seem to have some tolerance for it. Spraying Riddell groundsel with the ester form of 2,4-D at the rate of 1 to 1%, pounds, acid equivalent in 30 to 40 gallons of water to Figure 56. Riddell groundsel, Senecio riddellii. 31 the acre attains 90 to 100 percent kill, if applied in summer and late fall after rains. For spot spraying 0.4 percent Wetting solutions are most effective. Good kills have been obtained by spray- ing in the early flowering stage. Plants which were top-killed one year may send out new growth the following spring, but the shoots usually are abnormal and die after growing 3 or 4 inches. In general. the management is much the same as for S. longilobus. SOPHORA SECUNDIFLORA MESCAL BEAN, MOUNTAIN LAUREL, FRIJOLITO DESCRIPTION. Mescal bean is a shrub or small tree of the legume family. The odd-pinnate leaves are evergreen, leathery, dark green above and light green below. The showy bluish flowers have a sweet smell, and the fruit is a several- seeded, woody pod. The seed are bright orange to scarlet red and have a very hard seedcoat, Figures 57, 58 and 59. DISTRIBUTION. Mescal bean is most frequent on the Edwards Plateau and Trans-Pecos areas of Texas with records from Duval, Live Oak and Kleberg counties in the southern part of the State, Figure 60. This shrub extends into New Mexico on the west and Mexico on the south. SITES OF INFESTATION. This species occu; on hills and in canyons of the southern portion the Edwards Plateau. ~ Hardy 1935) stated that mescal bean exclusively on limestone soils. Huss (1954) fou it it most abundant on the rock ledges of the ou ,. lying foothills in his study in Real county. p also recorded stands on the divide lands of Ke Menard and Kimble counties. It is found mo commonly on canyon walls and along arroyos the Pecos River country and in canyons of Davis, Chisos, Glass and adjacent mountains. The seed of mescal bean are highly poisonous and contain a narcotic alkaloid, sophorine. Feeding tests of leaves havé demonstrated their toxicity to sheep, cattle and goats (Boughton and Hardy 1935). Cattle aré POISONOUS NATURE. very susceptible to the poison, while goats and sheep are more tolerant. The poison is not cumu- lative. l SYMPTOMS. Boughton and Hardy (1935), l found variation in the susceptibility of individual animals to mescal bean poisoning, but the poisoni; ing usually was not fatal except in cattle. They) . also stated that no danger exists from the conigl sumption of ripe seed, since the whole, undigested; seed are passed with the feces. Not all of t Figure 58. Flowering branch of Mescal bean. Cory (Boughton If ' Figure 59. Fruiting branch of Mescal bean. d pass through the alimentary canal of goats, owever, as many seed are ejected from the on the bed grounds while the animals are minating (Huss 1954). Poisoned sheep, when I ercised, show a stiffening of the hind legs, ortened stride and muscular trembling, and fall the ground, but they apparently recover after a rest period. Goats apparently were not poi- oned, but single feedings killed three out of lffour calves (Boughton and Hardy 1935). MANAGEMENT AND CONTROL. Since some ranchmen, especially on the Edwards Plateau, de- iapend on mescal bean for a certain amount of i browse for goats, management is of greater im- lffportance than control or eradication of the plant. The providing of supplemental feed, when other giforage is scarce, is recommended so that animals k-will not consume toxic amounts. u iXANTHIUM SPP. COCKLEBUR DESCRIPTION. Cockleburs are coarse, rough ciannual weeds with alternate, toothed or lobed leaves. The flowers are inconspicuous and im- erfect, the pistilate flowers developing into a . ur-like fruit. The fruit is usually 2-beaked, pivered with many spines and has 2 compart- ents, each containing a seed, Figure 61. Xan- ium is a genus of the composite family. Figure 60. Mescal bean, S0 pbom Jerz/ndiflora. DISTRIBUTION. Over 40 species of Xanthium are widely distributed, 5 of them in Texas. One species, X. spinosum, has triple spines in the axils of the leaves. SITES OF INFESTATION. Cockleburs are most frequent in disturbed and flooded areas of fields, pastures and roadways. They may be present in bar ditches, around earthen tanks, barnyard lots, old lake beds and river bottoms. POISONOUS NATURE. Cockleburs are mechan- ically injurious when consumed and also contain a toxic glucoside. The seed and young seedlings are more toxic than the older plants. Cocklebur poisoning may be fatal to hogs, cattle and sheep. SYMPTOMS. Animals poisoned by cockleburs show depression and general weakness, weak pulse, labored breathing and spasmodic move- Figure 61. Cocklebur, Xant/Jium 1p. 33 ments. Autopsies show inflamation of the stom- ach and intestines. This is accompanied by a thickening of the walls of the inflamed tissues. The liver is congested, bile is viscid and serum is present in the abdominal cavity. Vomiting is a symptom in pigs (Marsh et al. 1924). Poisoned animals should be kept warm; heart and respiratory stimulants and large doses of mineral oil may be given. MANAGEMENT AND CoNTRoL. Due to the structure and longevity of the burs, several years may be required to rid an area of this pest. Mowing, pulling or cutting can be practiced if the stand is not extensive. Control measures should be taken before the fruits are mature. Cocklebur plants can be killed readily by spraying with 2,4-D. Water solutions of the ester formulation applied at the rate o-f 0.1 per- cent (1,000 ppm) or about one-half pound per acre are very effective on young plants. As the plants mature, stronger and larger quantities of solutions are required to obtain a good kill. The amine forms of 2,4-D and combinations of 2,4-D and 2,4,5-T also obtain good kill. ZYGADEN US NUTTALLII NUTALL DEATH CAMAS, DEATH CAMAS DESCRIPTION. Nuttall death camas is a mem- Figure 62. Death camas, Zygadenus nuttallii. 34 e~ ber of the lily family (Liliaceae) and one several poisonous species of the genus Zygade It has long, somewhat curved leaves, an uni ground bulb, and flower stalks 1 to 2 feet Q The white flowers are borne in a dense terml cluster, Figure 62. The fruit is a dry ma‘ seeded capsule. Death camas is related to onions, and some species may be mistaken onions, especially in the preflowering stage growth. C DISTRIBUTION. This species is most pr lent in Texas on the eastern portion of the V wards Plateau, in the central and nort‘ prairies, and in post oak areas. It grows no " ward into Kansas and eastward into Tenne Other species have been reported for Texas are not frequent enough to be listed. i SITEs OF INFEsTATIoN. Nuttall death ca grows mostly in grasslands and open woodlaif It is frequent in marginal post oak woodland C may occur in open cedar or burned-over breaks. i POISONOUS NATURE. The toxicity of camas is thought to be due to an alkaloids it may be the result of an associated substa; Considerable work has been done on the va o; r range species, which vary in their poisonous p erties (Marsh and Clawson 1929a). Nuttall d camas probably is more poisonous than spi growing in the Western States (Marsh 19 which are reported more frequently in literal While most species of death camas are repof to be most toxic to sheep, Nuttall death cami equally poisonous to cattle and sheep. also are susceptible. All parts of the plant"; poisonous, even when dry. SYMPTOMS. Symptoms usually observed death camas poisoning are: salivating, na vomiting, lower temperature, weakness, _ cult breathing, coma and death. Poisoned animals should be treated at onset of the first symptoms and every 2 hou long as symptoms are present or recur. and respiratory stimulants should be given dermically. MANAGEMENT AND CONTROL. ‘The recogn, of death camas plants is important, and isol or keeping livestock out of heavily infested a, during the spring is a good practice. Since; plant is not usually abundant or widesprea Texas pastures, it may be controlled by grub Control is reported for some species by spra with the ester of 2,4-D at the rate of 3 po o per acre at the early bud stage of growth i] mont 1952). 11. PLANTS LESS COMMONLY TO ~ TO LIVESTOCK The following plants contain little toxic; stance, are not abundant or are not com ii grazed in enough quantity to cause poisog l. ever, when they are consumed in quantity livestock, high death losses may result. YSIA LYCIOIDES WHITEBRUSH, BEEBRUSH Whitebrush is a member of the Verbena fam- w i (Verbanaceae). It is frequent to abundant in a g»: West and South Texas and extends into Mexico and Mexico. A Water soluble toxin is present in white- . h. When grazed heavily by horses, white- h produces weakness and death. Horses Qbably have to graze it from 30 to 40 days ore symptoms develop (Mathews 1940c). As as known, horses, mules and donkeys are the animals affected by this species. Whitebrush has some value as a honey plant a limited value for browse. It has become a component of brush in some areas, especially are trees have been removed (McCully et al. .2)- ~RANTHUS SPP. "QCARELESS WEED, PIGWEED Careless weeds are annual weedy herbs and o; to the amaranth family (Amaranthaceae). are so commonly known that little descrip- is necessary, Figure 63. Nineteen species are i; re 63. Careless weed, Amamnt/am palmeri. recorded for Texas and some species can be found in almost every disturbed pasture or range area. They are common barnyard weeds in rich, moist soil. The growth form of the various species range from prostrate to branching upright. Most species, especially in early growth, are palatable to domesticated animals and are relished by swine; this is why the name “pigweed” often is applied. Careless weeds are not known to contain a poison, but cattle, horses and sheep have died from eating them in large quantities. Since young plants are very succulent, they may be consumed in large quantities and may cause severe bloat. There is a possibility that a high nitrate content is th)e cause of losses incurred (Durrell et al. 1952 . If conditions permit, careless weeds can be killed by spraying with 2,4-D or other herbicides. Hand pulling when the soil is moist or mowing or chopping localized areas are good control prac- tices. Areas supporting careless weeds frequently may be planted to supplemental feed crops. APOCYNUM ‘CANNABINUM DOGBANE, INDIAN HEMP Dogbane, Figure 64, is a perennial herb which grows along streams and in moist situations Figure 64. Dogbane, Apocynum cannabim/m. 35 in the Blackland Prairie and Edwards Plateau. Another species, A. androsaemifolium, on range areas of West Texas also is considered toxic. Dogbane is not considered a serious problem on the range since domesticated animals usually avoid these plants. The bitter, milky, rubber- containing juice presumably renders dogbane unpalatable and plants are grazed only when other forage isnot available. CICUTA CURTISSII AND CICUTA MACULATA WATER HEMLOCK AND SPOTTED HEMLOCK Water hemlock, Figure 65, is a perennial herb recorded for the Edwards Plateau of Texas and extends into the Southeastern States. Spotted hemlock is found in the Coastal Prairie area, the Blackland Prairie and the Edwards Plateau of Texas, and is widely distributed throughout east- ern North America. Cicutoxin is the poisonous principle of these plants and is found primarily in the roots and to a lesser degree in the young plants. Mature stems and leaves are not considered toxic. The toxin is poisonous to all warm-blooded animals, includ- ing humans. If abundance of infestation warrants, areas may be fenced or plants may be grubbed. If Figure 65. Spotted hemlock, Cicum maculata. 36 grubbed, care must be taken to remove all o, ground parts, as these are extremely poiso i under all conditions. The greatestdanger co in the spring when young plants may be gra Bohmont (1952) reports that Cicuto can be~_ trolled effectively with 2 pounds to the acre of ester of 2,4-D applied in the prebud stage. v; for localized areas, hemlock poisoning is no livestock problem in Texas. ii CLAVICEPS SPP. ERGOT Ergot is a fungus which grows systemi within the grass during the growing season produces overwinter bodies (sclerotia) which place some of the grain on the seed heads. favorable climatic conditions, enough of the rotia may develop to be poisonous, that is, to Q ergotism. While species of ergot grow on sevs-jf grasses, probably the most toxic form in grows on Dallisgrass and other species of palum. Ergot also may be associated with-y g i which may complicate toxic conditions. ‘ ergot also grows on cultivated grains, dry 1f, may be infected enough to cause ergotism. A Ergotoxine is the most toxic alkaloid in, and has some effect on the uterus and vessels. Ergotamine, a crystalline alkaloid, ca f contraction of the uterus and raises blood r‘ y t i sure. Neither of these is stable and ma changed into less active forms. Ergot may acute poisoning if a large quantity is eaten a time, or since its effects are cumulative, pois may develop if lesser quantities are eaten o] longer period. Experimentally, it has been st that a small amount of ergot is not injurio cattle being provided with a balanced ration. range cases in Texas are with cattle. Ergotism appears in different forms d, the variation in the action of the alkaloids. two common forms are gangrenous and ne both from the action of the drug on the c. lation. Gangrene affects those parts poor, blood supply: the extremities, tail, ears and The nervous form may exist in different f‘ of the body at the same time, beginning extremities and spreading toward the body," eating a possibility of circulatory changes. also may be disturbances in the digestive § There may be a loss of the special senses and tremors, ataxia and convulsions. Animals, quently die in convulsions. Abortion is consi another symptom of ergotism but whether ti true on the range is controversial. Most res on this with domestic animals has produced "tive results. Abortions do occur, however, i nervous form, but usually as one of the last s? toms, shortly before death. The placement of poisoned animals on hi free feed or pasture is the most practical m ment practice. If ergot-free range is not able, dry feed for 10 days or 2 weeks . ebrings recovery. Mowing with a high mower-bar of with a roto-cycle mower to cut off seed heads . is practiced where mowing is possible. Poisoned , animals ‘may be given tannin to neutralize ergot ‘ in the alimentary tract, and sedatives, such as 1. ~ chloral hydrate, may be given to nervous animals t‘ (Tehon et al. 1946). " 1i CONIUM MACULATUM POISON HEMLOCK, POISON PARSLEY f Poison hemlock, Figure 6'5, is a tall leafy- é" stemmed perennial. It occurs on the Edwards i Plateau and is fairly abundant in localities in '~ Bandera county. It also is common in the East- g ern and Western States and occasionally in the 5 Central States. ‘ The principle toxic substance in poison hem- § lock is coniine, an alkaloid, which is a heart depressant (Massy and Hatch 1943). All parts é of the plant, including the seed, are poisonous to {all types of domestic livestock. Poison hemlock is of greatest danger to livestock in the spring, gbut has low palatability and is not eaten to any * extent if good forage is available. The grubbing d. plants before seed maturity is practical if they iiare not too abundant. Local infested sites may be gisolated by fencing. Figure 66. Poison hemlock, Conizzm maculatum. Figure 67. Conyza, Conyza roulteri. CGNYZA COULTERI CONYZA, COULTER CONYZA Conyza is a herbaceous annual of the com- posite family, Figure 67 . It is frequent on range areas of the Trans-Pecos and may become abun- dant on heavily used and trampled areas and after flooding or during better rainfall years. It ex- tends into Colorado, California and Mexico. Sheep have been poisoned experimentally by feeding plant material totaling 3 percent of the body weight over a period of 3 days (Boughton 1942). Since conyza is potentially poisonous, good weed control practices should be applied on infes- ted sheep ranges. Mowing or spraying with chem- icals may be practical. Excellent kill of conyza has been obtained with both 2,4-D and 2,4,5-T in experimental trials. DELPHINIUM CAROLINIANUM DELPHINIUM VIRESCENS LARKSPUR The native larkspurs of Texas are perennial herbs with erect branching stems and alternate, lobed or divided leaves, Figure 68. Delphinium belongs to the crowfoot family (Ranunculaceae). D. virescens is distributed quite uniformly over Texas but is of greatest abundance on prairie 37 sites. D. caroliniainuow. is less frequent and wide- spread, and does not extend into the extreme northern, southern and western parts of the State. D. virescews is considered toxic to cattle (Durrell et al. 1952), but D. carolinianum is not known to be poisonous. Neither species, although often abundant, is considered hazardous on Texas ranges. They are included in this publication because of the potential danger when abundant and if grazed in quantity. HYPERICUM PERFORATUM ST. JOHNWORT, KLAMATH WEED St. J ohnwort is an upright, much-branched perennial growing to about 3 feet in height. In Texas, St. J ohnwort has been reported from the eastern portion of the State. It has long been known in the New England States and along the west coast and also grows in the Middle West and on the western range areas. St. J ohnwort also it reported as a disease-causing plant from Africa and Australia. It has been naturalized in the U. S. from Europe. St. Johnwort is toxic only to white or un- pigmented animals. The toxicity is due to the action of two florescent substances, hypericin and hypericum red. affected. Cattle, horses and sheep are Figure 68. Larkspur, Delp/ainium carolinianum. 38 Photosensitization, the most noticeable sy L tom of St. J ohnwort, is not known to occur Texas. The plants are not heavily grazed unl other forage is scarce. Mechanical or chemil control measures should be taken if the plat is abundant on pasture areas. KALLSTROEMIA HIRSUTISSIMA HAIRY CALTROP Hairy caltrop is a much-branched ann with long prostrate stems from a central u Figure 69. Caltrop is a member of the calt ~ family (Zygophyllaceae) and four other spe of the same genus are recorded for Texas. may be found in old fields, heavily grazed pastu g and disturbed areas over most of Texas a extends into Kansas, Colorado, Arizona an Mexico. * This plant was first suspected as the ca of cattle losses in the Trans-Pecos by Mathe (1944a). Mathews found by feeding that t plants were toxic to sheep and goats and possi cattle. The first symptoms of hairy caltrop soning, according to Mathews, is a weakness the hind legs with a knuckling of the fetlock joUiyp followed by posterior paralysis. Death y" ensue, especially if animals are exercised. Since hairy caltrop is an annual weed, gene i Figure 69. Hairy caltrop, Kallstroemia birszitirsima. practices to eliminate the Weed population and provide better forage is the best precaution. Turning hungry animals into heavily infested fields should be done only with close observation and caution. Poisoned animals should be kept quiet, fed and Watered. If possible, shade should be provided. ; MELILOTUS ALBA AND ' MELILOTUS OFFICINALIS WHITE SWEETCLOVER AND YELLOW SWEET- CLOVER Sweetclover is a valuable forage and soil im- provement crop but sweetclover hay or silage may cause extensive internal hemorrhages in cattle and sheep. Sheep have been observed to sicken and die after grazing green sweetclover. Poisoned animals should be kept quiet and may be given blood transfusions. Intravenous or intraperitoneal injections of hemostatic solutions _ should be given to speed blood coagulation (Milks 1949). ' Small or alternate feeding of alfalfa hay is indicated to prevent losses. lPHYLLANTHUS ABNORMIS ABNORMAL LEAFFLOWER Abnormal leafflower is an annual or short- lived perennial herbaceous plant With upright Figure 71. Bracken fern, Pteridium aquilinz/m var. prezzdocaudatum. stems and spreading or recurved branches, Figure 70. It is a member of the spurge family (Euphor- biaceae). Mathews (1945) demonstrated the tox- icity of this species from Culberson county to cattle, sheep and goats. He found a variation in the toxicity of the plant for different animals. Sheep and goats Were more resistant to the toxi- city than cattle. Collections of abnormal leaffloWers in Texas are from about 17 counties of the Plains areas, the Trans-Pecos, and South and South-central Texas, With questionable records from the Gulf Coast and Florida. This plant usually grows in sand or on sandy soils. As with most spurges, abnormal leafflower is relatively unpalatable. Supplemental feed or a change of pastures should alleviate further poisoning when cases develop from this plant. PTERIDIUM AQUILINUM var. PSEUDOCAUDATUM BRACKEN FERN Bracken ferns are large plants with perennial subterranean rhizomes and much-divided leaves, . a Figure 71. They are found primarily in the east- igurc 70. Abnormal leafflower, P/Jyllant/azz; abnormir. ern part 0f the State in Wooded and timber areas, 39 often in abundance. The species and its varieties, however, have a widespread distribution in wood- lands over much of the United States and also are found in Europe. Bracken fern is poisonous to cattle and horses and most cases of poisoning in the United States have been reported for the variety pubescens. This variety, known as western bracken fern, is common in Northwest United States. Although frequent on timber-range areas of East Texas, no records of poisoning are known definitely for the Texas variety. However, operators should know that it is potentially poisonous. Should poisoning occur, animals should be moved to bracken-free pastures or placed on feed. SARTWELLIA FLAVERIA SARTWELLIA Sartwellia is a yellow-flowered annual com- posite, Figure 72. It is frequent to abundant in local areas of Southwest Texas and adjacent New Mexico. Sartwellia often occurs in pure stands and is quite tolerant of alkaline soils. Mathews (1940) proved sartwellia to be poisonous, but in none of his experimental animals were lesions produced similar to those that prompted the investigation. Sartwellia has not been proved to be the cause of range livestock Figure 72. Sartwellia, Sartwellia flaveria. 40 losses, but since the plant is grazed and since » has been shown to be poisonous, its consumpti, by livestock should be watched. ‘ SESBANIA DRUMMONDII SESBANE, POISON BEAN i Sesbane is a perennial shrub of the legume .. family, Figure 73. Sesbane occurs in the Gulf Coast area and extends into the State along slug-_ *1 gish waterways and around wet sites. The plants are often in shallow water, at least for part of j the year. ; The seed of sesbane are poisonous to sheep, goats and cattle. Marsh (1929) states that about i an ounce of seed will kill a sheep and less than 1 2 ounces will kill larger animals. The primary symptoms of light cases of poisoning by sesbane i are depression, diarrhea and a rapid pulse. In l fatal cases, weakness and labored breathing pre-_ * cede death which ensues with little struggling. x Symptoms ordinarily appear about a day after I eating sesbane (Marsh 1920). 4 The major problem in sesbane-infested areas is to keep animals from browsing the plant and consuming the fruits during the winter. The removal of plants by mechanical means or killing with chemicals is a good precaution. Hazard sitesY also may be fenced to prevent browsing. Ample? Figure 73. Sesbane, Sesbania drummondii. i n ¢ - r supplemental feed during the winter usually ‘eeps animals from consuming toxic quantities. Laxatives are indicated to help poisoned ani- ymals in the elimination of the toxic material. SOLAN UM SPP. SILVERLEAF N IGHTSHABE, TROMPILLO, HORSE NETTLE, BLACK NIGHTSHADE, BUFFALO BUR Sixteen species of Solcmum are recorded for {Texas (Cory and Parks 1937) and at least fo-ur ‘species are potentially poisonous; Silverleaf énightshade, S. elaeagnifolium, Figure 74; and horse nettle, S. carolinense, are perennials with underground rootstocks. p Black nightshade, . nigrunz, and buffalo bur, S. rostratum, are an- nuals. Silverleaf nightshade is found over most of the range and pasture areas of Texas. Horse nettle, although not as widespread, grows in much the same habitats as silverleaf. Buffalo bur and black nightshade are annuals and often frequent flooded, badly trampled areas and old fields. ‘ L45”! n a The leaves and fruit of some species of Sola- azum contain an alkaloidal glucoside, solanime. It has been reported that only the leaves and een friut of silverleaf nightshade are toxic, but a -. lf was killed in experimental feeding with less ‘than 0.3 percent of body weight of. the dried fruit. w her calves became critically ill when fed only .1 percent of their body weight of the dried -\‘ w". t." t Figure 74. Silverleaf nightshade, Solanum - I agnifalium. fruit. Cattle have consumed enough silverlea nightshade to become poisoned, when crowde into areas where this plant was abundant, an may graze it accidentally or pick up the drie fruit along with cottonseed pellets, when fed on the ground. Chronic poisoning may result from prolonged eating of small quantities of horse nettle. If a considerable quantity is eaten in a short time, digestive disturbances, sleepiness and paralysis may occur (Hyatt et al. 1953). The green fruits of black nightshade are the most toxic part of the plant. Plants of buffalo bur are very spiny. A heavy or exclusive diet of these may cause mechanical irritation as well as possible poisoning. Due to the perennial underground parts, sil- verleaf nightshade and horse nettle are difficult to eradicate by mechanical means. To date, her- bicidal control has not been successful for these and buffalo bur and more experiments are needed on this method of control. Buffalo bur often grows on flooded flats and old fields; effective control can be had by mowing before fruits are formed. Black nightshade may be controlled by spraying with 2,4-D. Since the nightshade-s ‘are not readily grazed, management or stocking to insure sufficient good forage is the best precaution. \ Figure 75. Silky sophora, S op/aora sericea. T SOPHORA SERICEA SILKY SOPHORA Silky sophora is a herbaceous, low-growing legume with alternate, pinnately compound leaves, Figure 75. This species is common over much of West Texas and extends north to South Dakota and Wyoming, and west to Utah and Arizona. The seed, as with other species of Sophora, contain an alkaloid and thus plants are potentially toxic to livestock. Durrell et al. (1952) by experi- mental feeding had to force feed, but when fed even in quantity no illness resulted. Cattle poisoning in extreme West Texas, however, has been attributed to this plant. SORGHUM HALEPENSE. JOHNSONGRASS J ohnsongrass is an introduced perennial grass which has become naturalized in many sections of the State. Its value as a forage grass is becoming increasingly important. The conditions and treat- ments of poisoning from J ohnsongrass are much the same as given for the sorghums (Sorghum vulgare). SORGHUM VULGARE SORGHUMS The many varieties and strains of Sorghum vulgare are grain sorghums, forage sorghums, which include sweet sorghum and Sudangrass, and broom corn. Under certain conditions, the sorghums pro- duce a glucocide which yields several substances during digestion. One substance which may be formed is hydrocyanic (prussic) acid, a deadly poison. Since the conditions of poisoning are not entirely understood and established, they are omitted here but both green sorghum and cured sorghum hay may be involved. Poisoned animals become uneasy, stagger, fall, go into convulsions and breathe with increas- ing difficulty. The animal then becomes quiet, bloats and dies, usually within less than an ho-ur after eating the sorghum. Death appears to be due to the depressant effect of the hydrocyanic ficid on the respiratory and cardiac centers of the rain. The treatment of animals poisoned by hydro- cyanic acid is given under the discussion for wild plums and cherries (Prunus spp.). III. PLANTS ONLY OCCASIONALLY TOXIC TO LIVESTOCK Plants in the following list occur in Texas and are recorded as poisonous to livestock under certain conditions. Due to limited abundance or distribution, lack of palatability or to the fact 42 that they contain little toxic substance, they J not usually considered hazardous. Some of t ‘y are native, some are introduced. ' BACCHARIS PTERONOIDES ...... --BACCHA'_ CEPHALANTHUS OCCIDENTALIS ______________________ --BUTTONBU CORYDALIS AUREA----GOLDEN CORYDA DATURA METALOIDES __________ __JIMSONWE DATURA STRAMONIUM .......... "JIMSONWEEQS DESCURANIA PINNATA.-.-TANSY MUSTARB, LANTANA SPP ................................... "LANTANAF , MELIA AZEDARACH ______________ 1011mm BERRY. NERIUM OLEANDER ____________________ "OLEANDER NICOTIANA GLAUCA ..... ..... .-TREE TOBACCQ . PHYTOLACCA AMERICANA ...... --POKEWE PSORALEA TENUIFLORA .......... “sonar P RICINUS COMMUNIS .............. -_CASTOR BE p REFERENCES Beath, O. A., C. S. Gilbert, H. F. Eppson and Irene wt. 1953. Poisonous plants and livestock poisoning. Wyoi Agri. Expt. Sta. Bul. 324. 94 pp. p‘ Black, W. L. and K. W. Parker. 1936. Toxicity tests on I can rue. New Mexico Agri. Expt. Sta. Bul. 240. 14 -; Boughton, I. B. 1942. Correspondence with Loco Weed} search Laboratory, Texas Agri. Expt. Sta. .............................. .. and W. T. Hardy. 1935. Mescalbeani‘ pbora reczmdiflora) Texas Agri. Expt. Sta. Bul. 519. .............................. .. and W. T. Hardy. 1937. Toxicity of Q weed (Actinea odorata) for sheep. Texas Agri. Expt.‘ Bul. 552. 15 pp. i, Bohmont, D. W. 1952. Chemical control of poisonous it plants. Wyoming Agri. Expt. Sta. Bul. 313. 19 pp. i Clawson, A. B. 1933. The American groundsels, species Senerio as stock poisoning plants. Vet. Med. 28(3):10 f 11o. 1931. A preliminary report on the poi effects of bitter rubberweed (Actinea odomta) on sheep. j Agri. Res. 43(8):693-701. f .- Cory, V. L. 1930. A new loco from the Edwards Plateau, Y ' as. Rhodora 32z4-6. ‘ ...................... .. 1942. About angora goats and poisonous p; A Texas Agri. Expt. Sta. P.R. 772. 4 pp mimeo. 5' 1949. African rue (Peganum barmala) United States. Field and Laboratory 17(1):20-23. 1, .............................. ._ and W. H. Dameron. 1937. Range s' 3 of bitterweed. Sheep and Goat Raiser 7(11):8-9, 32-33..“ w. g .............................. .. and H. B. Parks. 1937. Catalogue V, flora of Texas. Texas Agri. Expt. Sta. Bul. 550. 180 ______________________________ .- and H. B. Parks. 1939. Dirymaria pbylla Woot. and Standl. Texas Agri. Expt. Sta. P.R. f I 3 pp mimeo. , ’ Coulter, j. M. 1891. Botany of Western Texas. U.S.D.A. _ _ j tributions U. S. National Herbarium 11(1) :1-588. a Couch, j. F. 1927. Poisonous constituents of richweed or p. snakeroot. Jour. Agri. Res. 35:547-576. .............................. ._ 1929. Tremetol, the compound that n‘ "Trembles" (milksickness). Amer. Chem. Soc. Jour.‘ 3617-3619. 1930. The toxic constituent of rayless ;~ l rod (Aplopappu: beterop/ayllur) jour. Agri. Res. 40:64. .............................. .. 1933. Trembles (or milksickness). U.S Cir. 306. 11 pp. .............................. .. 1936. The alkaloids of Lupinui boleig' Wats. Jour. Amer Chem. Soc. 58:1296-1299. ‘ i1 .................... .. 1940. Poisoning of livestock by plants that ‘roduce hydrocyanic acid. U.S.D.A. Leaflet 88. 4 pp. C. W. 1951. Control of orange sneezeweed with 2,4-D. our. Range Mgt. 4(1):11-15. Y , W. H. and T. j. jones. 1949. Poisonous plants of Georgia. Bul. Univ. of Georgia, School of Vet. Med. 59 (15):1-46. , ll, L. W., R. jenson and B. Klinger. 1952. Poisonous plants and injurious plants in Colorado. Colorado Agri. Expt. Sta. Bul. 412-H. s8 pp. a» C. E. and N. F. Peterson. 1921. Death camas. Ne- I vada Agri. Expt. Sta. Bul. 101. 31 pp. ................. .., M. R. Miller and L. R. Varvter. 1931. The tweek (Capnoide: careamz). Nevada Agri. Expt. Stal Bul. 121. 29 pp. p, t Service. 1940. Range plant handbook. U.S.D.A. Forest Service. - p G. S. and E. C. Carlyle. 1936. Locoine, the ‘poisonous ‘p principal of loco weed. Texas Agri. Expt. Sta Bul. 537. 18 PP~ . ..................... .. and S. H. Wender. 1944. Studies on toxic . substances of locoweeds, Artnzgalur Earlei and others. Texas Agri. Expt. Sta. Bul. 650. 23 pp. , F. C. 1930. Principal poisonous plants in Kansas. Kan- jsas Agri. Expt. Sta. Tech. Bul. 25. 67 pp. 1er, G. H., I. E. Newson and W. W. Robbins. 1918. A new .11 poisonous plant. Colorado Agri. Expt. Sta. Pub. No. ‘246. :16 PP- loch, j. N. and C. A. Brown. 1943. Poisonous plants and 7black widow spider of Louisiana. Louisiana Dept. of Con- éservation. Div. of Forestry, New Orleans. 133 pp. )4 , R. and W. M. Michael. 1935. White snakeroot pois- oning. Illinois Agri. Expt. Sta. Circ. 436. 12 pp. V , W. T., V. L. Cory, H. Schmidt and W. H. Dameron. 1931. fBitterweed poisoning in sheep. Texas Agri. Expt. Sta. Bul. - 433. 18 pp. ,1 A. L. 1945. Some poisonous plant problems of New iMexico. New Mexico Agri. Expt. Sta. Bul. 332. 23 pp. ’ ..................... _. 1949. Another poisonous species of Eupator- gium, (E. wrigbtii) Colorado-Wyoming Acad. Sci. jour. 4:52. man, G. O. 1945. A study of photosensitization of cattle in southeast Texas during 1953. Masters Thesis. Dept. _ Range and Forestry, Texas A. and M. College. Unpublished. ; man, W. T. and j. F. Couch. 1942. Plants poisonous to "livestock. U.S.D.A. Yearbook 1942. pp. 354-373. i, ...................... .. 1940. Correspondence with Loco Weed Re- fsearoh Laboratory. Texas Agri. Expt. Sta. :~< D. L. 1954. Factors influencing plant succession follow- ng fire in Ashe juniper woodland types in Real County, Tex- as. Masters thesis, Dept. Range and Forestry, Texas A. and M. College. Unpublished. , M. T., R. C. Brown and j. W. Herron. 1953. Some plants of Kentucky poisonous to livestock. Kentucky Agri. 8t Home Ec. Extension, Uni. of Kentucky. Circ. 502. 57 PP- S. E., W. H. Hill, and A. A. Bond. 1932. Control of the __ itterweed plant poisonous to sheep in the Edwards Plateau _- region. Texas Agri. Expt. Sta. Bul. 464. 23 pp. a ey, T. A. and R. H. Peebles. 1951. Arizona Flora. Univ. . ‘f of Calif. Press. Berkeley and Los Angeles. 10w, j. L. 1929. The poisoning of livestock by Drymaria a pacbyp/aylla. New Mexico Agri. Expt. Sta. Bul. 173. 13 pp. ully, W. G., j. A. Tynum and B. A. Perry. 1952. Reaction 1 of white brush to growth regulating herbicides. Texas Agri. Expt. Sta. P.R. 1462. 3 pp. mirneo. in gall, W. B. and Omer E. Sperry. 1951. Plants of the Big Bend National Park. National Park Service. U. S. Dept. i of Interior. U. S. Government Priniting Office. 209 pp. ‘ ke, R. H. F. 1931. The alkaloids of Senecio species. Can- f adian jour. Res. 5:651-659. ....................... .- 1938. The alkaloids of fumariaceous plants. frCanadian jour. Res. 16:81-90. h, C. D. 1919. Oak poisoning 0f domesticated animals. p U.S.D.A. Bul. 767. 36 pp. t ...................... .. 1920. A new sheep-poisoning plant of the southern states. U.S.D.A. Circ. 82. 4 pp. .............................. -- 1920. The whorled rnilkweed, a plant poisonous to livestock. U.S.D.A. Circ. 101. 2 pp. .............................. .- 1926. Rayless goldenrod (Aplopappur heter- op/ayllur) as a poisonous plant. U.S.D.A. Bul. 1391. 24 PP- ------------------------------ -. 1929. Stock-poisoning plants of the range. U.S.D.A. Bul. 1245. 75 pp. ------------------------------ .- 1929a. Trembles. U.S.D.A. Farmers Bul. 1953. 10 pp. -------------- and A- B. CIaWSOIL 1922. The death camas species, Zygadenu: parziculazur and Z. elegaur as poisonous plants. U.S.D.A. Bul. 1012. 25 pp. .............................. _- and A. B. Clawson. 1929. The loco-weed disease. U. S. Farmers Bul. 1054. 25 pp. .............................. .- and A. B. Clawson. 1929a. The st0ck-pois- oning death camas. U.S.D.A. Farmers Bul. 1273. 10 pp. .............................. -- and A. B. Clawson. 1934. rev. Larkspur or "Poison Weed." U.S.D.A. Farmers Bul. 988. 12 pp. .............................. .- A. B. Clawson, j. F. Couch and W. W. Eggle- ston. 1920. The whorled rnilkweed (Arclepiar galioider) as a poisonous plant. U.S.D.A. Bul. 800. 40 pp. .............................. .. A. B. Clawson, j. F. Couch and H, Marsh, 1921. Western sneezeweed as a poisonous plant. U.S.D.A. Bul. 947. 46 pp. .............................. .. A. B. Clawson and H. Marsh. 1914. Cicuta or water hemlock. U.S.D.A. Bul. 69. 27 pp. .............................. .. A. B. Clawson and G. C. Roe. 1928. Coyo- tillo (Karwinskia bumboltiana) as a poisonous plant. U.S. D.A. Tech. Bul. 29. 26 pp. .............................. .. G. C. Roe and A. B. Clawson. 1924. Cockle- burs (species of Xanthium) as poisonous plants. U.S.D.A. Bul. 1274. 24 pp. .............................. --‘G. C. Roe, and A. B. Clawson. 1926. Ray- less goldenrod (Aplopappu: beteropbyllus) as a poisonous plant. U.S.D.A. Bul. 1391. 24 pp. Massey, A. B. and R. D. Hatch. 1943. Poisonous plants. De- partment of Biol. Virginia Polytech. Inst. 36(8) :5-52. Mathews, F. P. 1932. Locoism in domestic animals. Texas Agri. Expt. Sta. Bul. 554. 36 pp. .............................. -. 1932a. Annual report, Loco Weed Research Laboratory for year ending in june 1932. Texas Agri. Expt. Sta. .............................. .. 1933. Poisoning of cattle by species of groundsel. Texas Agri. Expt. Sta. Bul. 481. 20 pp. .............................. .. 1933a. The toxicity of Baileya multiradiata for sheep and goats. jour. Amer. Vet. Med. Assn. 83(NS36- 5):673~679. .............................. .. 1934. Prilortropbe tagetinae and Prilortropbe gnapbaloder, two plants poisonous to sheep and cattle on the ranges of the Southwest. Texas Agri. Expt. Sta. Bul. 500. 13 pp. .............................. -- 1936. The toxicity of broomweed (Gutier- rizia mirrocepbala) for sheep, cattle and goats. jour. Amer. Vet. Med. Assn. 88(NS41-1) :55-61. .............................. .. 1937. Lechuguilla (Agar/e lecbeguilla). Poisoning in sheep, goats and laboratory animals. Texas Agri. Expt. Sta. Bul. 554. 36 pp. .............................. .. 1938. An experimental investigation of Le- chuguilla poisoning. Archives of Pathology 25:661-683. .............................. .. 1939. Poisoning in sheep and goats. Amer. Vet. Med. Assn. 93 (NS 46-3):168-175. .............................. -. 1945. A comparison of the toxicity of N0- tbolaena rinuata and N. sinuata var. coc/airenrir. Rhodora 47:392-395. .............................. .- 1940. The toxicity of Sartwellia flaveriae to goats. jour. Agri. Res. 61(4):287-292. ______________________________ .. 1940a. Poisoning in sheep and goats by sacahuiste (Nolina texana) buds and blooms. Texas Agri. Expt. Sta. Bul. 585. 19 pp. ______________________________ _- 1940b. The toxicity of red-stemmed peavine (Astragalu: emoryanur) for cattle, sheep and goats. jour. Amer. Vet. Med. Assn. 97(761):125-134. .............................. .- 1940c. The toxicity of Drymaria pacbyp/aylla for cattle, sheep and goats. Vet. Med. 35:255-260. 43 .............................. .. 1940d. Annual report Loco Weed Research Laboratory. Texas Agri. Expt. Sta. .............................. .. 1941. Annual report Loco Weed Research Laboratory. Texas Agri. Expt. Sta. i .............................. .. 1942. Fern (Notbolaena rinuata var. cre- nata) poisoning in sheep and goats and cattle. Texas Agri. Expt. Sta. Bul. 611. 15 pp, .............................. .. 1944. The toxicity of the ripe fruit of black- brush for sheep and goats. Texas Agri. Expt. Sta. Bul. 664. 16 pp. A .............................. .. 1944a. The toxicity of Kallrtroemia ‘hirsu- tirrinza (carpet weed) for cattle, sheep, and goats. Jour. Amer. Vet. Med. Assn. CV(10):152-155. ______________________________ __ 1945». The toxicity of a spurge (Pyllantbus almormir) for cattle, sheep and goats. Cornell Vet. 35(4): 336-346. Milks, H. J. 1949. Practical veterinary pharmacologY. materia medica and therapeutics. Alex Eger, Inc., Chicago. Moldenke, H. N. 1952. Aloysia, in Flora of Texas 3(1):62-66. University Press. S.M.U., Dallas. Moran, E. A., J. F. Couch and A. B. Clawson. 1940. Peganum barmala, a poisonous plant in the southwest. Vet. Med. 35: 234-235. Muenscher, W. C. 1951. Poisonous plants of the United States. Macmillan Co., New York. Muller, C. H. 1951. The oaks of Texas. Cont. Texas Res. Founda. 1(3):21-323. Norris, J. J. and D. A. Valentine. 1954. Principal livestock poisoning plants of New Mexico ranges. New Mexico Agri. Expt. Sta. Bul. 390. 78 pp. Pond, F. W. 1955. The chemical control of buckeye, Aerculu: arguta, on a Kerr county ranch. Masters thesis, Dept. Range 8r Forestry, Texas A&M College, unpublished. Price, D. A. and W. T. Hardy. 1953. Guajillo poisoning of sheep. Jour. Amer. Vet. Med. Assn. 122:223-225. Robbins, W. W., M. K. Bellue and W. S. Ball. 1951. Weeds of California. California Dept. of Agri. Documents Sec- tion, Sacramento. Sampson, A. W. and H. E. Malstrom. 1942. rev. Stock-poison- ing plants of California. California Agri. Expt. Sta. Bul. 44 593. 90 pp. ., Shahan, M. S. and W. T. Huffman. 1943. Diseases of? and goats. U.S.D.A. Farmers Bul. 1943. 59 pp. Shaw, A. 0., H. H. Biswell, J. E. Foster and R. W. Collins._ Some stock-poisoning plants of North Carolina. Nort -. lina Agri. Expt. Sta. Bul. 342. 12 pp. Sperry, O. E. 1949. The control of bitterweed (Artinea I on Texas Ranges. Jour. Range Mgt. 2(3):122-127. i‘ .............................. _. 1953. Rayless goldenrod——a poisono plant in Texas. Jour. Range Mgt. 6(1):6-10. .............................. .. and M. V. Anthony. 1953. Control of’, leaf broomweed with selective herbicides. Texas A i Sta. P. R. 1634. 3 pp. mimeo. _< .............................. .., P. H. Vardiman and R. G. Gray. 195 ,5 vine—a poisonous range plant in Texas. Texas A i Sta. P. R. 1474. 4 pp. it. Stevens, O. A. 1933. Poisonous plants and plant -<_ North Dakota Agri. Expt. Sta. Bul. 265. 30 pp. " Stoddart, L. A., A. H. Holmgren and C. W. Cook. portant poisonous plants of Utah. Utah Agri. E Special Report No. 2. 21 pp. - Tehon, L. R., C. C. Merrill and R. Graham. 1946. Illin -‘ poisonous to livestock. Illinois Agri. Ext. Serv. i 103 pp. " Tunnicliff, A. and V. L. Cory. 1930. Broad-leafed (Asrlepia: lazifolia) poisonous for sheep and goats, Amer. Vet. Med. Assn. 77(2):165-168. 4, Watt, J. M. and M. G. Greyer-Brandwijk. 1932. '17 cinal and poisonous plants of Southern Africa. gf Livingston, 16 and 17 Teviot Place, Edinburgh. f. Welch, H. and H. E. Morris. 1952. Range plants .-" livestock in Montana. Montana Agri. Expt. Sta. I f 35 pp. West, Erdman and M. W. Emmel. 1950. Some poisono in Florida. Florida Agri. Expt. Sta. Bul. 468. 47 ' Woodson, R. E. 1944. Notes on some North Ameri_ piads. Ann. Mo. Bot. Gardens 31:363-367. Van Es, L. L. F. Cantwell, H. M. Martin and J. Kram On the nature and cause of the “walking disease" 4,? western Nebraska. Nebraska Agri. Expt. Sta. Bul. 43.? w‘ . INDEX 1 h SPECIES Page SPECIES Page Abnormal leafflower ........... ......................... .- 39 Coyotillo ............................................................ .. 23 Acacia berlandieri ............................................ .. 4 Crazyweed ........................................................ .- 26 Actinea odorata .............................................. .. 21 Aesculus Mguta ______________________________________________ __ 5 Datum, metaloides .......................................... .. 42 Aesculus discolor ____________________________________________ __ 5 Datum, strawwnium ........................................ -. 42 Aesmlus spp_ ____________________________________________________ __ 5 Death camas .................................................... .. 34 African rue ______________________________________________________ __ 25 Delphinium carolinianum .............................. .. 37 Agave lecheguiua ____________________________ _____________ __ 6 Delphinium "virescens ...................................... ._ 37 Alkali weed ...................................................... .. 7 Deswraniw rinnaw ------------------------------------------ -- 42 Aloysia lycioides .............................................. .- s5 Desert baileya -------------------------------------------------- u 16 Amaranthiis spp. ______________________________________________ __ 35 Dogbane ---------- ----------------------------------------------- -- 35 Aplopappus heterophyllus ______________________________ __ 7 DTi/mfl/Tia Paffhil/Phil/ua ------------------------------------ -- 17 Apocynum awrdrosaemifolium ........................ -. 36 “Apocynum cannabinum __________________________________ __ 35 Earle loco .......................................................... -- 12 Asclepias latifolia ............................................ -- 8 Emory loco """"""""""""""""""""""""""""""""""""""" " 13 i-Asclepias subverticillata ................................ .. 9 Ergot """""""""""""""""""""""""""""""""""""""""""""""" " 36 Asdem-as verticiuata ______________________________________ __ 11 Eupatorzeam rugosuam ...................................... -- 18 wtragalus argillophilus ................................ .- 11 Euphorbw Spp‘ """""""""""""""""""""""""""""""""""""""""""" " 19 stragalus earlei ................................................ .. 12 Flourensia cemua 19 fAstragalus emoryanus .................................... .. 13 F .. rt """""""""""""""""""""" " 32 {a . . r130 1 o ............................................................ .. stragalus mollzsszmus .................................. .. 14 5481101991148 "uttauiflnus ---------------------------------- -- 13 Garbancillo ...................................................... .- 15 Astrayalus wootovzz .......................................... .. 15 Golden corydalis ______________________________________________ __ 42 g Groundsel ................................................... _- 30, 31 acchamis pteronoides .................................... _- 42 Guajillo .......................................................... 4 aileya, mult-iradiata ________________________________________ _. 16 Gutierrezia microcephala ................................ .- 20 eebrush .......................................................... .- 35 itter sneezeweed ____________________________________________ __ 21 Hairy caltrop .................................................... -. 38 géBitterweed ........................................................ __ 21 Helenium nudiflorum ...................................... .. 21 ‘éBlackbrush .............................. _____________________ __ 19 Helenium tenuifolium .................................... .- 21 gBlack nightshade .............................................. ._ 41 Hemlock ........................................................ ..36, 37 fBracken fern .................................................... .. 39 Horse nettle ...................................................... .. 41 {Broad-leafed milkweed __________________________________ __ 8 Horsetail milkweed .......................................... _. 9 ' Broomweed ........................................................ __ 20 Hydrocyanic acid BUttOIIbUSh ______________________________________________________ __ 42 Prunus spp. .................................................. -- 27 Buckeye ____________________________________________________________ __ 5 Sorghum halepense ...................................... .- 42 Buffalo bur _______________ _____________________________________ _, 41 Sorghum vulgare ........................................ .. 42 Hymenoocys odorata ................................... .. 21 areless Weed _________________________________________________ __ 35 Hypericum perforatum .................................. .. 38 astor bean ...................................................... .. 42 . ; eeeeeeeeeeeeeeeeeeeeeeeeeeeeee a 42 ififliiiefiemp eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee ~ China berry ...................................................... -. 42 Igocoma """""""""""""""""""""""" " 21 Chokecherry .................................................... .. 27 ‘ ‘ """""""""""""""""""""""" " i§Cljcuta curtissii ................................................ -- 36 Jimmy fern ______________________________________________________ __ 25 ECzcuta maculata ............................................... .. 36 Jimmy Weed ____________________________________________________ __ 7 riaclaviceps Spp" -------------------------------------------------- -- 36 Jimsgnweed ______________________________________________________ __ 42 Wcoclflebur ---------------------------------------------------------- -- 33 Johnsongrass .................................................... -. 42 ' 012mm maculatum .......................................... __ 37 WWO» flfiiuliwi ________________________________________________ ._ 37 Kallstroevwvia hirsutissima .............................. .. 38 orydalis aurea .............................................. .. 42 Karwinskia humboldtiana .............................. .. 23 5 ulter conyza . .............................................. .. 37 Klamath weed .................................................. .. 38 45 SPECIES Page Lambert loco .................................................... .- 26 Lantana spp. .................................................... .. 42 Larkspur .......................................................... _. 37 Lechugilla ..................................................... 6 Loco weeds o ' Astra-gains argillophillus ............................ -. 11 Astragalus ea/rlei ........................................ .- 12 Astragalus emery/anus ................................ -- 13 Astragalus mollissimus ..................... 14 Astmgalws wootoni .................................... _. 15 Oxytropis lambertii ........................... ....... .- 26 Melia azedarach .............................................. .- 42 Melilotus alba .................................................. -- 39 Melilotus officinalis ....................... .§ ............... -. 39 Mescal bean ...................................................... ._ 32 Milkweeds _ Asclepias latifolia ........................................ -. 8 Asclepias subverticillata ................. ......... -. 9 Asclepias verticillata ........................ ...... .. 11 Mountain laurel .............................................. -- 32 Mustard ............................................................. .. 42 Nerium oleandea" .............................................. .. 42 Nicotiana qlauca .............................................. -- 42 Nightshade ...................................................... -1 41 Nolina texana ............................................. 24 Notholaena sinuata var. cochisensis ............ .- 25 Nuttall death camas ........................................ ._ 34 Nuttall peavine ................................................ -- 13 c Oaks .................................................................. -- 29 Oleander ............................................................ -- 42 Oxytropis lambertii ........................................ .. 26 Paper-flower __________________________________________ _-; ......... -- 28 Peavines Astragalus emoryanus ................................ ._ 13 Astragalus nuttallianus .............................. .- 13 Peganum harmala ............................................ _- 26 Photodynamic plants Agave lecheguilla ........................................ -- 6 Hypericum perforatum .............................. -- 38 Nolina texana .............................................. ._ 24 Phyllanthus abnormis .................................... .- 39 Phytolacca americana .................................... __ 42 Pigweed ............................................................ _. 35 Point loco .......................................................... .. 26 Poison bean ...................................................... .- 40 Poison hemlock ................................................ .. 37 Poison parsley .................................................. .- 37 Pokeweed .............................. ........ ..... 42 Prunus spp. .......................................... ..l..;.-'.-..‘;‘i‘.’. 27 46 SPECIES . ‘ Psilostrophe gnaphalodes .............................. Psilostrophe tagetinae .................................. .. Psomlea tenuiflora. ........................................ .- Pteridium aquilinum var. pseudocaudatum“ Purple loco ................................................ Purplehead sneezeweed _____________________________ __ Quercus havardii ........................................ __ Quercus texana __________________________________________ __ Rattle-Weed loco ......................................... _. Rayless goldenrod ______________________________________ __ Red-stemmed peavine ................................. __ Richweed ............................ _______________________ __ Ricinus communis _______________________________________ __ _ Riddell groundsel _______________________________________ __ Sacahuista __________________________________________________ __ ‘i Sartwellia flaveria _________________________________________ ___ Scurf pea ..................................................... __ Senecio longilobus .......................................... Senecio riddellii ___________________________________________ __ Sesbania drummondii ................................ __ p Shinnery ......................................................... .. Y Shin oak .......................................................... , Silky sophora ................................................ Silverleaf nightshade ................................... ._j Slinkweed ........................................................ Snakeweed ...................................................... a Sneezeweed ____________________________________________________ _§ Solanum carolinense ______________________________________ Solanum elaeagnifolium ................................ Solanum nigmm ____________________________________________ Solomum rostratum ........................................ Sophora secundiflora ................................ Sophora sericea .............................................. Sorghum halepense ........................................ Sorghums ........................................................ .§ Sorghum vulgare ............................................ j Spanish oak ............................................ >rb .... ..1j Spotted hemlock ......... ............................... Spurges ........................................................... ..3 St. Johnwort ..... f. ...... .................................. .. Q Sweetclover ................................................... _. i Tansy mustard ............................................. Tarbush ......................................................... Thickleaf drymary ...................................... Threadleaf broomweed ................................. -.?-" Threadleaf groundsel ................................... .5} Tree tobacco .................................................. Trompillo ................................................... .:. j Turpentineweed ..................................... .; .... .. a a r hemlock .................................................. -_ 36 bruéh ............ ....................................... -- 35 I e snakeroot .............................................. -. 18 _ gte sweetclover ................ --'_ ......................... -- 39 lrled milkweed ............................................ __ 11 _ Md cherry ...................................................... -- 27 _= dplum .......................................................... .- 27 SPECIES Page SPECIES Page Woolly groundsell .............................................. -- 30 Woolly loco ................................................... 14 Xa/lzthium spp. ................................................ -. 33 Yellow sweetclover .......................................... .- 39 Yellowed-flowered loco .................................... .- 11 Zygadenus nuttallii ...... -- 34 47 Ad‘? ~ r Texas Agricultural Experiment Station, R. D. Lewis, Diféctor, College Statizfim, Texas ’\