A83-l29-8,000-L18O BULLETIN NO. s93 1 2g M, i) _ W“ “ t‘ t? “Y DIVISION OF PLANT Plxfiflb AND PHYSIOLOGY Plants Susceptible or Resistant to Cotton Root Rot and their Relation to Control AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS T. O. WALTON, President TAs of February 1, 1929. STATION STAFF} A DMINISTRATION: A. B. CoNNER, M. S., Director R. E. KARPER, M. S., Vice-Director J. M. SCHAEDEL, Secretary M. P. HoLLEMAN, JR., Chief Clerk J. K. FRANcKLow, Assistant Chief Clerk CHESTER HIGGS, Executive Assistant C. B. NEBLETTE, Technical Assistant CHEMISTRY; " _ G. S. FRAPs? Ph. D., Chief; State Chemist S. E. AsBURY, M. S., Assistant Chemist E. C. CARLYLE, B. S., Chemist _ WALDo H. WALKER, Assistant Chemist VELMA GRAHAM, Assistant Chemist H. S. OSGOOD, M. S., Assistant Chemist T. L. OGIER, B. S., Assistant Chemist J. G. EvANs, Assistant Chemist ATHAN J. STERGES, B. S., Assistant Chemist G. S. CRENsRAw, A. B., Assistant Chemist JEANNE M. FUEGAS, Assistant Chemist HANs PLATENiUs, M. Sc., Assistant Chemist HORTICULTURE: HAMILTON P. TRAUB, Ph. D., Chief ———————————-—, Berry Breeder RANGE ANIMAL HUSBANDRY: J. M. JONEs, A. M., Chief; Sheep and Goat Investigations J. L. LUSH, Ph. D., Animal Husbandman; Breeding Investigations STANLEY P. DAvis, Wool Grader ENTOMOLO GY: F. L. THOMAS, Ph. D., Chief; State Entomologist H. J. REINRARD, B. S., Entomologist R. K. FLETcRER, M. A., Entomologist W. L. OWEN, JR., M. S., Entomologist FRANK M. HULL, M. S., Entomologist J. C. GAiNEs, JR., M. S., Entomologist C. J. ToDD, B. S., Entomologist F. F. BIBBY, B. S., Entomologist _ S. E. McGREGoR, JR., Acting Chief Foulbrood Ins ector OTTo AcKENsEN, Foulbrood Inspector AGRONOMY: E. B. REYNoLDs, M. S., Chief R. E. KARPER, M. S., Agronomist; Grain Sorghum Research _ C_. MANaELsDoRF, Sc. D., Agronomist; in charge of Corn and Small Grain Investi- gations D. T. KILLOUGH, M. S., Agronomist; Cotton Breeding H. E. REA, B. S., Agronomist; Cotton Root Rot Investigations W. E. FLINT, B. S., Agronomist PUBLICATIONS: A. D. JAcKsoN, Chief VETERINARY SCIENCE: *M. FRANcis, D. V. M., Chief H. SCHMIDT, D. V. M., Veterinarian F. E. CARRoLL, D. V. M., Veterinarian PLANT PATHOLOGY AND PHYSIOLOGY J. J. TAUBENHAUS, Ph. D., Chief W. N. EZEKIEL, Ph. D., Plant Pathologist an Laboratory Technician .W. J BACK-I, M. S., Plant Pathologist J. PAUL LUsK, S. M., Plant Pathologist B. F. DANA, M. S., Plant Pathologist FARM AND RANCH ECONOMICS: L. P. GABBARD, M. S., 'ef W. E. PAULsoN, Ph. D., Marketing Researc Specialist C. A. BoNNEN, M. S_., Farm Management Research Specialist _ V. L. C0RY, M. S., Grazing Research Botanii J. F. CRiswELL, B. S., Assistant; Farm Record and Accounts **J. N. TATE, B. S., Assistant; Ranch Records and Accounts RURAL HOME RESEARCH: JEssiE WRITAcRE, Ph. D., Chief MAMIE GRiMEs, M. S., Textile and Clothin Specialist EMMA E. SUMNER, M. S., Nutrition Specialis SOIL SURVEY: _ **W. T. CARTER, B. S., Chief E. H. TEMPLIN, B. S., Soil Surveyor T. C. REiTcir, B. S., Soil Surveyor L. G. RAosDALE, B. S., Soil Surveyor BOTANY: i———————, Chief SiMoN E. WOLFF, M. S., Botanist SWINE HUSBANDRY: FRED HALE, M. S., Chief DAIRY HUSBANDRY: O. C. CoPELAND, B. S., Dairy Husbandman POULTRY HUSBANDRY: R. M. SHERWOOD, M. S., Chief ***AGRICULTURAL ENGINEERING: MAIN STATION FARM: G. T. McNEss, Superintendent APICULTURE (San Antonio): H. B. PARKS, B. S., Chief A. H. ALEX, B. S., Queen Breeder FEED CONTROL SERVICE: F. D. FULLER, M. S., Chief S. D. PEARCE, Secretary J. H. ROGERS, Feed Inspector W. H. W0oD, Feed Inspector K. L. KIRKLAND, B. S., Feed Inspector W. D. NORTHCUTT, JR., B. S., Feed Inspecto SIDNEY D. REYN0LDs, JR., Feed Inspector P. A. MooRE, Feed Inspector SUBSTATIONS No. 1, Beeville, Bee County: R. A. HALL, B. S., Superintendent No. 2, Troup, Smith County: P. R. JoiINsoN, B. S., Act. Superintendent No. 3, Angleton, Brazoria County: R. H. STANsEL, M. S., Superintendent No. 4, Beaumont, Jetferson County: R. H. WYcI-IE, B. S., Superintendent No. 5, Temple, Bell County: HENRY DUNLAVY, M. S., Superintendent B. F. DANA, M. S., Plant Pathologist H. E. REA, B. _S., Agronomist; Cotton Root Rot Investigations SiMoN E. WoLFF, M. S., Botanist; Cotton Root Rot Investigations No. 6, Denton, Denton County: P. B. DUNKLE, B. S., Superintendent No. 7, Spur, Dickens County: R. E. DIcKs0N, B. S., Superintendent W. E. FLINT, B. S., Agronomist No. 8, Lubbock, Lubbock County: D. L. JoNEs, Superintendent FRANK GAiNEs, Irrigationist and Forest Nurseryman No. 9, Balmorhea, Reeves County: J. J. BAYLEs, B. S., Superintendent No. l0, Feeding and Breeding Station, near Colle e Station, Brazos County: R. M. irEnwooo, M. S., Animal Husband man in Charge of Farm L. J . McCALL, Farm Superintendent No. 11, Nacogdoches, Nacogdoches County: H. F. M0RRIs, M. S., Superintendent **No. 12, Chillicothe, Hardeman County: J. R. QUINBY, B. S., Superintendent _ **J. C. STEPHENS, M. A., Junior Agronomist No. l4, Sonora, Sutton-Edwards Counties: W H. DAMERoN, B. S., Superintendent E. A. TUNNICLIFF, D. V. ., . S., Veterinarian _ V. L. CoRY, M. S., Grazing Research Botanis **O. G. BABCOCK, B. S., Collaborating Entomologist O. L. CARPENTER, Shepherd No. 15, Weslaco, Hidalgo County: W. H. FRIEND, B. S., Superintendent _ SHERMAN W. CLARK, B. S., Entomologist W. J. BACH, M. S., Plant Pathologist No. 16, Iowa Park, Wichita County: E. J. WILsoN, B. S., Superintendent _ J. PAUL LUsK, S. M., Plant Pathologist Teachers in the School of Agriculture Carrying Cooperative Projects on the Station: G. W. ADRIANcE, M. S., Associate Professor of Horticulture S. W. BILSING, Ph. D., Professor of Entomology _ V. P. LEE, Ph. D., Professor of Marketing and Finance D. ScoATEs, A. E., Professor of Agricultural Engineering _ _ H. P. SMITH, M. S., Associate Professor of Agricultural Engineering R. H. WILLIAMs, Ph. D., Professor of Animal Husbandry A. K. MAcKEY, M. S., Associate Professor of Animal Husbandry J. S. MOGFORD, M. S., Associate Professor of Agronomy *Dean, School of Veterinary Nledicine. **In cooperation with U. S. Department of Agriculture. ***In cooperation with the School of Agriculture. SYNOPSIS Root rot attacks at least two hundred and seventy-four species of cultivated plants. Many important field crops, vege- tables, fruit trees, berries, and ornamentals are affected. The cultivated species listed as resistant to root rot number one hundred and thirty-five, including the few separate species of grasses which are named. Wheat, oats, corn, sorghum, rice, barley, and all other members of the grass family appear to be immune to the disease. Root rot causes extensive damage to many important crops such as cotton, legumes, sweet potatoes, pears, figs, and grapes and results in extremely large losses. The widespread distri- bution of root rot and the susceptibility of so many useful plants account for the great importance of the disease in Texas. Yields are reduced, which increases costs of produc- tion; land values are thus depreciated and agricultural de- velopment limited. Root rot also affects many plants not ordinarily cultivated, including weeds, native plants, and trees. Two hundred and forty-four species are listed as susceptible and sixty-six as resistant. These susceptible species of wild plants are im- portant from the standpoint of the general problem of control. Short-lived plants or annuals support the fungus only during their period of life. Long-lived species or perennials carry the fungus over longer periods of time. Where these weeds are present, root root cannot be controlled without controlling the weeds. Solong as susceptible perennial weeds persist in cul- tivated fields or along the borders of such fields, root rot will be able to survive and attack the susceptible crops. Native vegetation is found affected with root rot. When virgin land is brought into cultivation, the root-rot fungus spreads from the diseased roots of native plants to the roots of cultivated crops. CONTENTS PAGE Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5 Symptoms of‘ Root Bot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5 Methods of Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6 Explanation of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . '2 Discussion of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1O Cultivated Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10 Non-cultivated Plants . .‘ . . . . . . . . . . . . . .' . . . . . . . . . . . . . . . . . . . 11 Root Rot on Newly Cleared Land . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1.3 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1b References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . l . . . . . . . . . . . . . 17' BULLETIN NO. 393 FEBRUARY, 1929 PLANTS SUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT AND THEIR RELATION TO CONTROL J. J. TAUBENHAUS, B. F. DANA AND S. E. WOLFFi‘ The root-rot disease, caused by the fungus Phymatotrichunz omni- vorum (Shear) Duggar, is the most destructive plant disease of Texas. In regions in which root rot occurs nearly everyone is interested in knowing which plants are susceptible and which plants are resistant to this disease. The grower of field crops is in need of information which will enable him to select the proper crop to be grown, or to plan a profitable rotation which will at the same time control or reduce the losses from this disease to a. minimum. Similarly, truck and fruit growers are in search of resistant crops in order to realize profitable returns. And no less interested are the nurserymen and home owners, who desire to select planting materials that will live. To gather accurate information on the number of plants affected and the extent of injury produced by root rot, a state-wide survey, covering a period of years, was made. From the information now on hand, lists have been prepared of the species which are either free from, or subject to the disease. The species listed have been carefully examined when- ever they were found in places where root rot was present. Continued freedom from disease in these areas has been considerd sufficient reason for placing such plants in the highly resistant or immune class. Time has not permitted a study of all possible host plants. IIowever, important cultivated species and a large proportion of the no11-cultivated species found in root-rot areas are represented. The present list also includes the plants first tested by Taubenhaus and Killough (l). These, together with all other species studied, are classed as resistant or sus- ceptible on the basis of present knowledge. SYMPTOMS OF ROOT ROT Root rot is usually noticed only when infected plants actually begin to wilt. Yet if plants which are growing next to wilted ones are pulled out, the root systems of these apparently healthy plants are often found already covered with the yellowish to buff-colored mats of the root-rot fungus. This fungus growth on the roots is the cause of the root-rot disease, and plants cannot exhibit symptoms of root rot unless the fungus has attacked their roots or underground parts. After *The writers are indebted to the late Professor H. Ness, Chief of the Division of Botany, Agricultural Experiment Station, College Station, and to Mr. V. L. Cory, Grazing Research Botanist Substation No. 14, Sonora, for identifications of many of the plant species included in this study. 6 BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION the fungus has started to grow on the roots, plants may still appear quite normal for a week or more While the roots are being destroyed. iIt is only when the roots of the diseased plants are thoroughly involved that symptoms usually appear on parts above ground. In early stages of infection of many herbaceous plants the upper leaves may wilt slightly while the lower leaves appear normal. This wilting of the upper leaves is especially noticeable early in the morning when normal plants have recovered from the effect of the natural wilt- ing that was brought about by the heat of the previous dayr. The lower leaves on such affected plants also wiltand droop by the following day. Other herbaceous plants in certain stages of infection may shed their leaves quickly, reducing the transpiration surface, then later recover and continue growth at the growing points. These plants often remain alive during the growing season. Less frequently the whole plant wilts in one day. The wilted leaves may recover their normal position or may remain in this wilted and collapsed condition and never recover. Within twenty to forty hours the wilted foliage dies, becomes crisp, and appears brown or blackened as though scorched by fire. The roots of an infected plant are at this time completely covered with the yellowish or bufi mats of fungus threads. Furthermore, the cortex of the roots, particularly of the tap root, has become softened and may be readily peeled off with the least pressure of the finger. If an infected plant remains in the" ground for some time the cortex rots off and all that is left of the tap root is a woody stub. Shrubs and trees react in a manner similar to that of herbaceous plants. It is not possible to determine from an examination of the tops of plants when the roots are first infected. Especially on trees with large root systems, the disease may be present on the roots for many months before infection and growth of the fungus are suspected. Only after the disease has considerably invaded the root system, do affected shrubs or trees begin to shed their leaves. This shedding may be gradual or rapid, depending on how completely the root system has become involved. Occasionally, trees shed their foliage during one season but do not die until the following year. When either a woody or an herbaceous plant is killed by root rot the entire root system is not necessarily involved at one time. The greatest destruction of the root system is usually of the tap root itself and of the portions of the laterals which join the tap root. The large laterals away from the zone of infection are not necessarily involved at this time, and may remain alive for months after the top of the plant has died. The root-rot fungus may slowly spread along these- living laterals, and in this way be carried to underground parts of succeeding plants. METHODS OF STUDY A survey was made of selected areas throughout the state. Attention _ was paid not only to the wilted or dead plants, apparently suffering from PLANTS SUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT 7 root rot, but also to plants that were apparently not injured though they were growing in root-rot spots. Rather extensive and yet careful surveys were possible because of the positive and easily distinguished symptoms of the root-rot disease. With the majority of host plants there is a characteristic sudden wilt- ing of the aerial portions following invasion of the root systems by the fungus. In all oases, however, the presence of root rot Was verified by examination of the underground parts of the plants for the yellow- ish strands or-mats of the fungus. These are always present on dis- eased plants and can ordinarily be seen by the unaided eye. The roots were examined in the field with a hand lens and were then sent to the laboratory, where the microscope was used to check the field deter- minations. A few species have also been tested by inoculation experiments as a more positive means of determining resistance or susceptibility. As opportunity permits, these tests will be continued to include all im- portant species. EXPLANATION OF TABLES The species reported in this study are listed below in two groups, the cultivated plants in Table 2 and the non-cultivated plants in Table 3. In general, those given in Standardized Plant Names (6) are listed as “Cultivated Plants.” This group includes not only the common crops but also other plants often planted in home grounds or gardens. All the so-called weeds and native plants, with the exception of those brought into cultivation, are placed in a second group designated as “Non-cultivated Plants.” The organization of the two lists is identical and is essentially an alphabetical arrangement of species according to» common names. This arrangement is used because of the familiarity of the public and grow- ers in general with the common names. As far as possible, the com- mon names and the principle of Word formation as used in Standard- ized Plant Names (6) are adopted. Other names are taken from various floras and guides; while, in a number of instances, they are original and descriptive in character. For each kind of plant, the botanical name and citation are supplied in the second column for the benefit of nurserymen, technical workers, and others desiring the in- formation. Small (3) is followed for names included in his flora. Others are obtained from Bailey (5), North American Flora (1), Brit- ton’ and Brown (2), J epson (7), Rehder (8) and Schulz (9). All family names are used according to the arrangement and terminology in Small (3). In the last column of Tables 2 and 3, each plant is rated as to its susceptibility or resistance to root rot. Species found very susceptible are followed by a double p-lus (+ -l-) sign. Those showing slight to moderate susceptibility are indicated by a single plus (—l—) sign. Those not recognized as susceptible after observation and testing are desig- nated by a minus (—) sign and tentatively may be considered resist- ant to root rot. 8 BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION Fio". 1——Vegetable hosts for root rot. A. Carrots killed by root rot introduced at the point marked by the stake. B. Healthy and diseased carrots. Note fungous growth on the surface of the diseased carrot. C. Diseased beet with fungus covering the surface “of the lower half. PLANTS SUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT 9 Fig. 2‘—Cultivated hosts for root rot. A. Diseased peach showing typical symptoms._ B. Two healthy and one diseased California Prive-ts. C. Sweet potatoes showing a tangltd mass of vines killed by the disease. D. ‘Nilted cotton plant. E. Pigeon pea, showing two plants diseased and one healthy. 1O BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION DISCUSSION OF TABLES Cultivated Plants Many important facts can be gleaned from a study of the lists of , cultivated and non-cultivated plants presented in Tables 2 and 3. Among the cultivated plants listed in Table 2 (see also Figures 1 and 2), may be mentioned some important groups of susceptible species. Cotton ranks high in importance in Southern agriculture. Its extreme susceptibility to root rot results in heavy losses to the grower. Many other members of the Mallow (Malvaceae) family to which cotton be- longs are also highly susceptible, indicating that this character may be present throughout the family. Likewise, members of the Legume or Bean familyfFabaceae) show very high susceptibility. Wlhere root rot is prevalent and severe, the susceptibility of legumes practically prevents their general use as field crops. The elimination of these valuable feed crops and soil builders is a serious handicap to the agri- culture of the affected regions. Susceptibility in trees and especially in long-lived, slow-growing fruits, nuts, and ornamentals is of considerable importance. In the orchard the life of fruit trees such as pears, apples, quinces, cherries, peaches, figs, mulberries, and persimmons is so short in the presence of root rot as to discourage all but the most persevering orchardists. No less serious is the disease in the long-lived ornamentals. Elms, maples, locusts, cottonwoods, and chinaberries should never be planted in affected locations. Certain spruees, pines, and arborvitae give dis- appointing results, which are more keenly felt because the loss of such shrubs and trees often ruins the landscape effect. Also new plantings in the same locations usually succumb, making the replacement of the specimens lost an uncertain procedure. Other ornamental trees and shrubs such as roses, spireas, privets, and the lilacs are also susceptible and unsatisfactory in locations where root rot is prevalent. Many important vegetable crops are highly susceptible. The fact that these are short-lived serves to reduce, but does not eliminate the losses. Among the important and at the same time very susceptible vegetables are common beets, sugar beets, carrots, parsnips, eggplants, turnips, sweet potatoes, beans, peas, and cowpeas. Extensive growing of these may be unprofitable when root rot is present. Small fruits are seriously injured loy root rot. and raspberries scarcely become established before they succumb if they are set in locations where root rot is prevalent. The absence of these small fruits in communities where root rot is general is noticeable. In attempting to classify the horticultural varieties of certain genera, it was found impossible to assign them to definite species. This was particularly true with grapes and roses. The cultivated varieties of grapes and roses appear highly susceptible. Material is being as- sembled for a test of resistance and determination of species in these groups and in certain other genera where the same situation exists. Grapes, blackberries, _ Lgiiullgu. i. .1......;- . PLANTS SUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT 11 From the number of important cultivated crops mentioned above and others included in the list, it will be seen that the disease is a serious limiting factor in the agriculture of the regions where root rot occurs. The task of finding satisfactory substitutes is indeed a difficult one. The parasite attacks such a large number of species and With such virulence that search for resistance is impractical except with a very few of the more important crops. iCultivated plants naturally resistant or immune include the large family of grains and grasses and several other families, among which are the Melon (Uucurbitaceae), Onion (Alliaceae), Lily (Liliaceae), Mint (Lamiaceae), Asparagus (Olonvallariaceae), and Palm (Areas;- ceae). The grains and grasses appear to be immune. They are not killed by the disease even when grown among. diseased plants of other species. The small grains, sorghum of all kinds, hay, and grass crops are of value in rotations. Small grains are harvested early, which per- mits cultivation of the land for Weed eradication to be carried on dur- ing the dry hot weather when such operations are most effective. Sorghums, as row crops, allow continued cultivation for weed control. Grasses do not carry root rot, but perennial weeds may exist in meadow land and perpetuate the disease for an indefinite time. Corn does not seem to be affected, but on the average farm the cultivation given corn is not sufficient to keep- weeds in check. In many cases, the fungus has a better opportunity to live over on susceptible weeds in corn fields than in the average cotton field. Altogether rotations with the grains and grasses, because of their resistance and the way in which they lend themselves to culture for weed control, offer the best avenue for lessening the ravages of the disease in cotton and other susceptible crops. Melons, onions, and asparagus are mentioned above as showing high resistance and immunity. It is probable that they can be used to advantage as general crops only in irrigated sections where the disease is sometimes serious. A number of other cultivated species are listed as resistant. Some are valuable as ornamentals; others have a limited agricultural value in the areas where root rot occurs. Non-cultivated Plants The susceptible non-cultivated species belong to many families (see Table 3, and Figures 3, 4i and 5.) Some of these are perennials and harbor root rot from year to year and, if not disturbed, will carry infection indefinitely. The Common Tievine (Ipomoea trifida), Soft Groundcherry (Physalis mollis), Silver-leaved Nightshade (SOZQHUTYL eilaeagnrifoliztm), Horse-nettle (Solarium carolinense), and Hog Potato (Hofinzanseggia densiflora), are examples of perennials that are at- tacked but are capable of persisting for a considerable period in a dis- eased condition. Some of these develop an extensive and vigorous underground root system which furnishes an extended food supply for the root-rot parasite. Others have storage organs which may be at- 12 BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION Fig. 3——Perennial weeds subject to root rot. A. Soft Groundcherry (Physalis mollis). B. Common Tievine (Ipomoea trifida). C, D, E, and F. Trumpet Four-0’clock (Aclezl santhes Zongiflora). G. Silver-leaved Nightshade (Solarmm elaeagnifolium). PLAlNTS SUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT 13 Fig. 4—Hog Potato (Hofitnzavascgg/ia denls/iflora). A. Growth habit. B and E. Tuberous enlargements 0f roots. C. Diseased plant. D. Portion of plant bearing pods. 14 BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION Fig. 5—Annua1 weeds subject to root rot. A. Spiny Sow-thistle (Sonchu-s asper). B. Ragweed Parthenium (Partheniuvn hysterophorus). C. Common Cocklebur (Xawthiuvn italicum). D. Hairy Spurge (Cham/aesyce malaca). ~- root rot is less active. ~ 1>r*‘11'>w'\ -»;»-~_». »- . - ‘1-1-,»»-,-=,.-_ 11y*fl)y'»"n~»—rv <>oy ean . . . . . . . . . . . . . . . . Soja max Piper . . . . . . . . . . . . . . . . Fabaceae . . . . . . . . . . . . + + ipearmint . . . . . . . . . . . . . . . Mentha spicata L . . . . . . . . . . . . . Lamiaceae . . . . . . . . . . . —— ipinach, Common . . . . . . . . Spinacia oleracea L . . . . . . . . . . . . Chenopodzaceae . . . . . . . + + ipirea, Vanhoutte. . . . . . . Spiraea vanhoutiei Zabel. . . . . . . Rosaceae . . . . . . . . . . . . . + ipruce, Norway. . . . Picea excelsa Link . . . . . . . . . . . . Pinaceae . . . . . . . . . . . . . + pruce, Red . . . . . . . . . . . . . P. rubra Link . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + 1 pruce, Tigertail . . . . . . . . . P. polita Carr . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + " purge, Cypress . . . . . . . . . Tithymalus cyparissias (L.) _ . _ Hill . . . . . . . . . . . . . . . . . . . . . . . Euphorbiaceae . . . . . . . . —— Spurge, Flowering . . . . . . . . Tithymalopsis corollata (L.) F Kl. & Garcke . . . . . . . . . . . . .. “ _ . . . . . . . . . . . . . —~ * Squash . . . . . . . . . . . . . . . . . Cucurbila maxima Duchesne. . . Cucurbitaceae . . . . . . . . —— -< Squash, Summer Crookneck . . . . . . . . . . . . C. pepo L., var. condensa Bailey “ _ . . . . . . . . . . . . . + itock, Common . . . . . . . . . . Maithiola incana R. Br . . . . . . . . Brasszcaceae . . . . . . . . . -— "strawberry (Cult. var.). . . Fragaria chiloensis Duchesne. . . Rosaceae . . . . . . . . . . . . . — , "itrawflower . . . . . . . . . . . . . Helichrysum bracfeatum Andr.. . Carduaceae . . . . . . . . . . —— j mndrops, Rose . . . . . . . . . ; Harlmamiia rosea (Ait.) _ _ G. Don . . . . . . . . . . . . . . . . . . . Epzloblaceae . . . . . . . . . + Sunflower, Ashy . . . . . . . . . Helianthus mollis Lam... . . . . . . Carduaceae . . . . . . . . . . + _; Sunflower, Common . . . . . . H. annuus L . . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + . Sunflower, Maximilian. . . . H. maximilianii Schrad.. . . . . . . “ . . . . . . . . . . . . . + i; Sunflower, Silverleaf . . . . . . H. argophyllus T. & G . . . . . . . . . “ . . . . . . . . . . . . . + .-i Sunflower, Swamp . . . . . . . H. anguslifolius L . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Sweetclover, Annual Yellow . . . . . . . . . . . . . . . . Melilotus indica All . . . . . . . . . . . Fabaceae . . . . . . . . . . . . + + Sweetclover, Biennial f; e ow . . . . . . . . . . . . . .. M. oflicinalis Lam . . . . . . . . . . . .. “ . . . . . . . . . . . .. + + 'r~ Sweetclover, Hubam. . . . . M. alba Desr., var. annua Coe.. “ . . . . . . . . . . . . . + + ‘ ‘. Sweetclover, White . . . . . . . M. alba L . . . . . . . . . . . . . . . . . . . . “ . .._. . . . . . . . . . . + + _, Sweetgum . . . . . . . . . . . . . . . Liquidambar styraciflua L.. . . . . Altingiaceae . . . . . . . . . . + + e Sweetgum, Formosa . . . . . . L. formosana Hance . . . . . . . . . . . “ . . . . . . . . . . . . . + + Sweetpotato . . . . . . . . . . . . . I omoea batatas Lam . . . . . . . . . . Corwolvulacae . . . . . . . . + + c; Sweet-sultan . . . . . . . . . . . . Cesntaurea moschata L . . . . . . . . . . Carduaceae . . . . . . . . . . + f Sweet-William . . . . . . . . . . . Dianthus barbafus L . . . . . . . . . . . Caryophyllaceae . . . . . . . —— 5 Tallowtree, Chinese . . . . . . Sapium sebiferum (L.) Roxb.. . . Euphorbiaceae . . . . . . . . + + ? Tamarix, French . . . . . . . . . Tamarix gallica L . . . . . . . . . . . . . Tamaricaceae . . . . . . . . + 1 Thoroughwort, Sweet. . . . . Eupalorium ageratifolium DC. . Carduaceae . . . . . . . . . . + 3 Tobacco, Common . . . . . . . Nicotiana labacum L . . . . . . . . . . . Solanaceae . . . . . . . . . . . + *Numerous varieties grown in Texas. BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION 24 Table 2.—Relative Susceptibility of Cultivated Plants to Root Rot-Continued _ _ Relative Common Name Species or Botanical Name Family Suscepti- bility Tomato . . . . . . . . . . . . . . . . . Lycopersicon lycopersicon _ ._ Ka . . . . . . . . . . . . . . . Solanaceae . . . . . . . . . .. + Tree, Tung-oil . . . . . . . . . . . Aleurlies fordu Hemsl.. . . . . . . . Euphorbiaceae . . . . . . . . + Tulgerose . . . . . . . . . . . . . . . . Polianthes tuberqsa L . . . . . . . . . . Leucojageae . . . . . . . . . . — Tuliptree . . . . . . . . . . . . . . . Lzrlodpndron tulzpifera L . . . . . . . Magnolzaceae . . . . . . . ~ . . + Turnip . . . . . . . . . . . . . . . . . Brassica rapa L. . ._ . . . . . . . . . . . Brasszcaceae . . . . . . . . . + Valerian, Common . . . . . . . Valerzana officmalzsL . . . . . . . . . Valerianaceae . . . . . . . . —- Vegetable-oyster._ . . . . . . . . Tragopogon porrzfollus L . . . . . . . Cichoriaceae . . . . . . . . . + + Velvetbean, Deering . . . . . . Mucuna deeringianum (Bort) Small. . . . . . . . . . . .. Fabaceae . . . . . . . . . . .. + Verbena, Dakota . . . . . . . . . Verbena bipznnatzfidaNutL. . . . Verbenaceae . . . . . . . . . . + Verbena, Rose . . . . . . . . . . . V. canadensis (L.) Britton. . . . . “ . . . . . . . . . . . . . —~ Violet, Sweet . . . . . . . . . . . . Viola odorata L . . . . . . . . . . . . . . . Violaceae . . . . . . . . . . . . — Wallflower, Common. . . . . Cheiranthus cheiri L . . . . . . . . . . . Brassicaceae . . . . . . . . . — Walnut, Black . . . . . . . . . . . Juglans nigra L.. .. . . . . . . . . . . Juglandaceae . . . . . . . . . + Walnut,_ Japanese . . . . . . . . J. sieboldiapa Magum. ._ . . . . . . . . “ _ . . . . . . . . . . . . . + Wandering-Jew . . . . . . . . . . Trarjescantza flymmenszs Vell.. . Commelznaceae . . . . . . . —— Watercress . . . . . . . . . . . . . . Rorzpa nasturtiam (L.) Rusby. Brassicaceae . . . . . . . . . — Watermelon (All var.) . . . . Cztrullus vulgarzs Schragl . . . . . . . Cucurbitaceae . . . . . . . . — Waxmallow, Drummond. . Malvaviscus druinmondu T. & G Maluaceae . . . . . . . . . . . + Weigela, Pink . . . . . . . . . . . Wqzgela rosea Lindl . . . . . . . . . . . . Caprifolzaceae . . . . . . . . + Wheat (Cult. yar.) . . . . . . . Trztzcum aestivum L . . . . . . . . . . . Poaceae . . . . . . . . . . . . . — Wild-sarsaparilla . . . . . . . Aralia nudicaulis L. . .. . . . . . . . . Araliaceae . . . . . . . . . . . + Willow, Babylon Weeping. Salzx babylonica L. . . . .. . . . . . . . Salicaceae . . . . . . . . . . . + Willow, Black . . . . . . . . . . . S. nigra L . . . . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Witch-hazel, Common. . . . Hamamelis virginiana L . . . . . . . . Hamamelidaceae . . . . . . + Woodsorrel, Common. . . . . Oxalis acetosella L . . . . . . . . . . . . . Oxalidaceae . . . . . . . . . . - Woodsorrel, Violet . . . . . . . Ionoxalis uiolacea (L.) Small . . . “ . . . . . . . . . . . . . — Yam, Common . . . . . . . . . . Dioscorea sativa . . . . . . . . . . . . Tamaceae . . . . . . . . . . . . + Yaupon . . . . . . . . . . . . . . . . . Ilex vomiloria Ait . . . . . . . . . . . . . Aquifoliaceae . . . . . . . . . ~— Yucca, Common . . . . . . . . . Yucca filamentosa L . . . . . . . . . . . Dracaenaceae . . . . . . . . . —- Zinnia, Common . . . . . . . . . Zinnia elegans Jacq . . . . . . . . . . . Carduaceae . . . . . . . . . . — PLANTS SICISCEPTIBLE OR. RESISTANT TO COTTON ROOT ROT Table 3.—Relative Susceptibility of Non-cultivated Plants to Root Rot 25 Common Name Abutilon, Berlandier . . . . . . Abutilon, Texas . . . . . . . . . . Abutilon, Wright . . . . . . . . Acanthochiton, Soft . . . . . . Alternanthera, Prostrate. . Amaranth, Green . . . . . . . . Amaranth, Prostrate. . . . . Amaranth, Slender . . . . . . . Amaranth, Spiny . . . . . . . . Anemone, Carolina . . . . . . . Angelico . . . . . . . . . . . . . . . . Aster, Drummond . . . . . . . Aster, Grass-leaved . . . . . . . Aster, Hairy . . . . . . . . . . . . . Aster, Purple . . . . . . . . . . . . Aster, Slender . . . . . . . . . . . Aster, Spiny . . . . . . . . . . . . . Aster, Tansy . . . . . . . . . . . . Aster, Western SilveryT. . . Atriplex, Bushy. . . . . . . . . Atriplex, Common . . . . . . . Bahia, Absinthium- leaved . . . . . . . . . . . . . . . . Balloonvine, Small-fruited Balloonvine, Woolly . . . . . . Berlandiera, Lyre-leaved. . Berlandiera, Texas . . . . . . . Bindweed, Gray . . . . . . . . . Bindweed, Hedge . . . . . . . . Bindweed, Hoary . . . . . . . . Bitterweed . . . . . . . . . . . . . . Bladderpod, Many- flowered . . . . . . . . . . . . . . Bladderpod, Slender . . . . . . Blazingstar, Slender . . . . . . Boerhaavia, Hairy . . . . . . . Boerhaavia, Linear~leaved. Boerhaavia, Prostrate. . . . Boerhaavia, Upright . . . . . . Boltonia, Panicle . . . . . . . Breweria, Pickering . . . . . . Broomweed . . . . . . . . . . . . . Buffalo-bur . . . . . . . . . . . . . . Buttercup, Wedge-leaved. Buttonweed . . . . . . . . . . . . . Calthrop, Hairy . . . . . . . . . Cardinal-feather . . . . . . . . . Carrot, Wild . . . . . . . . . . . . Chaetopappa . . . . . . . . . . . . Chenopodium, Whitish. . . Chervil . . . . . . . . . . . . . . . . . Chickweed, Common. . . . . Chickweed, Mouse-ear. . . . Cladothrix, Shrubby . . . . . . Cladothrix, Woolly... . . . . Clotbur, Great..... . . . . .. Clotbur, Spiny . . . . . . . . . . . Clover, BurT . . . . . . . . . . . . Cocklebur, Common . . . . . . l Species or Botanical Name Abutilon berlandieri A. Gray. . . A. lexcnse T. & G A. wrightii A. Gray. ._ . . . . . . . . . Acanthochiton wrightiz Torr. . . . . Altemanthera repens (L.) Kuntze Amaranthus retroflexus L A. blitoides S. Wats.. . . . . ..... A. hybridus L . . . . . . . . . . . . . . . . A. spinosus L . . . . . . . . . . . . . . . . Anemone caroliniana Walt.. . . . Ligusticum canadense (L.) Britton . . . . . . . . . . . . . . . . . . . . Aster drummondii Lindl . . . . . . . . A. poaceus Burgess . . . . . . . . . . . A. hirtellus Lindl . . . . . . . . . . . . . . A. purpuratus Nees . . . . . . . . . . . A. exilis Ell A. spinosus Benth.. . . . . . . . . .. M achaeranthera tanacetifolia (HBK.) Nees . . . . . . . . . . . . . . Aster sericeus Vent . . . . . . . . . . . . . Atriplex canescens (Pursh) James . . . . . . . . . . . . . . . . . . . . . A. opposilifolia S. Wats.. . . . . .. Bahia absinlhifolia Benth.. . . . . Cardiospermum microcarpum C. corimlum L . . . . . . . . . . . . . . . . Berlandiera lgrala Benth . . . . . . . B. lexana DC Convolvulus hermannioides . Gray . . . . . . . . . . . . . . . . . . . C. repens L . . . . . . . . . . . . . . . . . . C. incanus Vahl . . . . . . . . . . . . . . Helenium tenuifolium Nutt. . . . . Lesquerelja polyantha Schlecht. . L. gracilis (I-Iook.) S. Wats. . . . . Laciniaria acidota (Engelm. 8c Gray) Kuntze. . . Boerhaavia hzrsuta L.. . B. linearifolia A. Gray. B. decumberzs Vahl . . . . . . . . . . . . B. erecta L . . . . . . . . . . . . . . . . . . . Boltonia diflusa Ell. . . . . . . . . . .. Breweria pickeringii ( . A. Curtis) A. Gray. . . . . Gutierrezia lexana (DC) T. & G. Solanum rostratum Dunal Ranunculusfcunciformis Small. . Diodia teres Walt . . . . . . . . . . . . . Kallstroemia hirsutissima Vail. . Acalypha lindheimeri uell. Arg . . . . . . . . . . . . . . . . . Daucus pusillus Michx. . . . .. . Chaetopappa parryi A. Gray. Chenopodlum albqscens Small. . . Chaerophyllum temturieri Hook. Alsine media L Cerastium vulgatum L . . . . . . . . . . Cladothrix suflruticosa (Torr.) S. Wats . . . . . . . . . . . . . C. lanuginosa Nutt . . . . . . . . . . . Xanthjum speciosum Kearney. . X. sninosum L Medicago arabica All . . . . . . . . . . Xanthium ilalicum Moretti. . . . Family Relative Suscepti- bility** M alvaceac . . . . . . . . . . . (i u Ranunculaceae. . . . . . . Ammiaceae . . . . . . . . . . Carduaceae . . . . . . . . . . n: Carduaceae . . . . . . . . . . Sapindaceae . . . . . . . . . . i‘ u Carduaceae . . . . . . . . . . Brass icaceae . . . . . . . . . 6 G Cargiuaceae . . . . . . . . . . Allionlaceae . . . . . . . . . . .. u c: Carduaceae . . . . . . . . . . Convolvulaceae. . . . . . . . Carduaceae..... . . . . .. Solanaceae _ . . . . . . . . . . Ranunculaceae . . . . . . . Rubiaceae . . . . . . . . . . . . Zygophyllaceae Euphorbiaceae . . . . . . . . . Ammiaceae . . . . . . . . . . Carduaceae . . . . . . . . . . Chenopodiaceae Ammiaceae . . . . . . . . . . Alsiriaceae . . . . . . . . . . . Fabaceae. .- . . . . . . . . . . Ambroszaceae . . . . . . . . . ll ++++ ++++ + ++ ++ +++++++ llI+++++++ ++++++ lll++++ l+l+++ ++++++ **Double plus _(+ +) sign highly susceptible, single plus (+) moderate to slight suscepti- bility, minus (—) immune TThose occasionally cultivated or resistant. indicated by T. 26 BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION Table 3.—Relative Susceptibility of Non-cultivated Plants to Root Rot-Continu ed _ _ Relative Common Name Species or Botanical Name Family Suscepti- bility Coneflower, Large- _ _ flowered . . . . . . . . . . . . . . Rudbeckza grandlflora _C. C. Gm_el . . . . . . . . . . . . . . . . Carduaceae . . . . . . . . .. + Coriander . . . . . . . . . . . . . . . Bzfora amerzcana (DC.) W_ats.. .' . . . . . . . . . . ._ . . . . . . Ammiaceae . . . . . . . . . . + Cowherh . . . . . . . _. . . . . . . . . Vaccarza vaccar_ia_(L.) Britton. . Caryophyllaceae . . . . . . —— Cranesbill, Carolina . . . . . . Geranium carolzmanum L . . . . . . Geraniaceae . . . . . . . . . . — Cranesbill, Texas . . . . . . . . G. texanum_ (Trel.) Heller . . . . . . “ . . . . . . . . . . . . . — Croton, Capitate . . . . . . . . . Croton capztatus Michx.. . . . . . Euphorbiaceae . . . . . . . . + Croton, Dwarf . . . . . . . . . . . C. berlandieri_Torr . . . . . . . . . . . . “ . . . . . . . . . . . . . + Croton, Engelmann . . . . . . C. engelmanmi Ferguson . . . . . . . “ . . . . . . . . . . . . . + Croton, Lindheimer . . . . . . C. lindheimerianus Scheele. . . . . “ . . . . . . . . . . . . . + Croton, Silvery . . . . . . . . . . C. argymnthemus Michx.. . . . . . “ . . . . . . . . . . . . . + Croton, Single-fruited. . . . C. monanjhogynus Michx . . . . . . . “ . . . . . . . . . . . . . + Croton, Texas . . . . . . . . . . . C. texensls (Kl.) Muell. Arg.. . . “ . . . . . . . . . . . . . + Croton, White . . . . . . . . . . . C. leucophyllus Muell. Arg.. . . . “ . . . . . . . . . . . . . + Daisy, Berlandier . . . . . . . . Berlandzera dealbata (T. & G.) Small . . . . . . . . . . . . . . . . . . . . . Carduaceae . . . . . . . . . . + Daisy, Mountain . . . . . . . . Melqmpodium cinereum DC.. . . “ . . . . . . . . . . . . . + Daisy, Western . . . . . . . . . . Bellls mtegrifolia Michx . . . . . . . . “ . . . . . . . . . . . . . + Daisy-fleabane, Western. . Erigeron bellidiastrum Nutt.. . . . “ . . . . . . . . . . . . . + Datura, Sacred? . . . . . . . . . Datura meteloidesDC . . . . . . . . . . Solanaceae . . . . . . . . . . . + Daubentonia . . . . . . . . . . . . Daubentonia longzfolia _(Ca_v.) DC._ . . . . . . . . . . . . . . . . Fabaceae . . . . . . . . . . . . + Ditaxis, Low . . . . . . . . . . . . Dztaxzs humilzs (Engelm. & Gray) Pax . . . . . . . . . . . . . . . . . Euphorbiaceae . . . . . . . . + Dock, Berlandier . . . . . . . . Rumer berlandieri Meisn . . . . . . . Polygonaceae . . . . . . . . . —- Dock, Swamp . . . . . . . . . . . R. verlicillatus L . . . . . . . . . . . . . . “ . . . . . . . . . . . . . — Dock, Yellow . . . . . . . . . . . . R. crispus L . . . . . . ._ . . . . . . . . . . . “ . . . . . . . . . . . . . + Dragonroot . . . . . . . . . . . . . Muricauda dracontzum (L.) mal . . . . . . . . . . . . . . . . . . . . . Araceae . . . . . . . . . . . . . — Elder, Marsh . . . . . . . . . . . . Iva ciliala Willd . . . . . . . . . . . . . . Ambrosiaceae . . . . . . . . . + Encelia . . . . . . . . . . . . . . . . . En_celia subarislata A. Gray. . . . Carduaceae. . . .. . . . . . . + Eriogonum, Long-leaved. Erzogonum longifolium Nutt. .. . Polygonaceae . . . . . . . . . —- Eryngo, Hooker . . . . . . . . . . Eryngium hookeri Walp . . . . . . . . Ammiaceae . . . . . . . . . . + Eryngo, Wright . . . . . . . . . . E. wrightii A. Gray . . . . . . . . . . . “ . . . . . . . . . . . . . + Evolvulus, Silvery . . . . . . . Evolvulus ilosus Nutt . . . . . . . . . Convolvulaceae . . . . . . . . + Evolvulus, Soft . . . . . . . . . . E. mollis mall . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Evolvulus, Tufted . . . . . . .. E. alsinoides L. . . . . . . . . . . .. . . . “ . . . . . . . . . . . . . + Eysenhardtia . . . . . . . . . . . . Eysephardiia azporphoides HBK. Fabaceae . . . . . . . . . . . . + False-dandelion, Leafy- Silzlzas carolinzana (Walt) stemmed. Raf . . . . . . . . . . . . . . . . . . . . . . . Cichoriaceae . . . . . . . . + False-dandelion, Many- stemmed. _ S. multiqaulis (DC.) Greene. . . . “ . . . . . . . . . . . . . + False-dandelion, Rough. . S. grandzflora (Nutt.) Greene.. . “ . . . . . . . . . . . . . + False-mallow, American.. . Malvastrum americanum (L.) Torr . . . . . . . . . . . . . . . . . . . . . . Malvaceae . . . . . . . . . . . + False-mallow, Red . . . . . . . M. coccineum (Pursh) A. Gray.. “ . . . . . . . . . . . . . + False-mallow, Slender~ leaved . . . . . . . . . . . . . . . . M. leptophyllum A. Gray . . . . . . “ . . . . . . . . . . . . . + False-mallow, Spiked. . . . . M. spicatum_(L.) A. Gray. . . . . “ .. . ._ . . . . . . . . . + Flax, Prairie . . . . . . . . . . . . . Linum lewiszi Pursh . . . . . . . . . . Linaceae. . . . . . . . . . . . . + Flower-of-an-hour . . . . . . . . Hibiscus lrionum_L . . . . . . . . . . . . Malvaceae . . . . . . . . . . . + Four-o’clock, Trumpet. . . . Acleisanthes longzflora A. Gray. Allioniaceae . . . . . . . . . . + Frog-fruit, N arrow-leaved. Phyla lanceolata (Michx.) _ Greene. ._ . . . . . . . . . . . . . . . . . . Verbenaceae . . . . . . . . . . —— Frog-fruit, Shrubby . . . . . . . Lippla gengmata HBK . . . . . . . . “ . . . . . . . . . . . . . —— Frog-fruit, Wedge-leaved. Phyla cunezfolia (Torn) Greene. “ . . . . . . . . . . . . . — Gaillardia . . . . . . . . . . . . . . . Gaillardia chrysantha Small. . . . Carfluaceae . . . . . . . V. . . + Garlic, Meadow . . . . . . . . . . Allium canadense L.. . . . . . . . . . Allgacege . . . . . . . . . . . . —- Gaura, Scarlet . . . . . . . . . . . Gaura coccinea Pursh . . . . . . . . . . Epzlobzaceae . . . . . . . . . + Gaura, Small-flowered . . . . G. parviflora Dougl . . . . . . . . . . . . “ . . . . . . . . . . . . . + Gaura, Wavy-leaved . . . . . G. sinuata Nutt . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Gayoides . . . . . . . . . . . . . . . . Gayoides crispum (L.) Small. . . . Malvaceae . . . . . . . . . . . + Gilia, Needle-leaved . . . . . . Gilia rigidula Be'nth . . . . . . . . . . . Polemoniaceae . . . . . . . . + Golden-aster, Berlandier. . Chrysopsis bprlandieri Greene.. . Carduaceae . . . . . . . . . +- Goldenrod, Downy . . . . . . . Soligiago petlolaris Ait . . . . . . . . . “ . . . . . . . . . . . . . + Goldenrod, Slender Showy. S. rlgidiuqcula (T._& G.) Porter. “ . _. . . . . . . . . . . . + Goosefoot, Bosc . . . . . . . . . . Chenopodzum bosczanum Moq.. . Chenopodlaceae . . . . . . . + Goosefoot, Narrow-leaved. C. leptophyllum (Moq.) Nutt. . . “ . . . . . . . . . . . . . + r i" PLANTS SUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT Table 3.—Relative Susceptibility of Non-cultivated Plants to Root Rot—-Continued l Relative Common Name Species or Botanical Name Family Suscepti- 1 ity Grasses . . . . . . . . . . . . . . . . . Various sp_ecies* . . . . . . . . . . . . . . Poaceae . . . . . . . . . . . . . — Groundcherry, Hoary. . .. . Physalzs vlscosa L . . . . . . . . . . . . . Solanaceae . . . . . . . . . . . + Groundcherry, Purple- _ flowered . . . . . . . . . . . . . . Qumcula lobata (Torr.) Raf. . . . “ . . . . . . . . . . . . . + Groundcherry, Soft . . . . . . . Physalis mollzs Nutt . . . . . . . . . . . “ . . . . . . . . . . . . . + Groundcherry, Texas. . . . . P. tezcana Rydb . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Groundsel, Balsam . . . . . . . Senecio balsamitae Muhl.. . . . . . Carduaceae . . . . . . . . . . + Gum-plant, N arrow- _ _ leaved . . . . . . . . . . . . . . . . Gflflddja lanceolata Nutt . . . . . . . _ “ _ . . . . . . . . . . . . . + Hawkweed, Long-bearded. Hieraclurn longipilum Torr.. . . . Czchorzaceae. . . .. . . . . . + Heliotrope, Smooth . . . . . . . Helutropzum glabrzusculum _ » _ ray . . . . . . . . . . . . . . . . . . . Helzotropiaceae . . . . . . . + Hibiscus, Heartleaf . . . . . . . Hibiscus cardiophyllus A. Gray. Malvaceae . . . . . . . . . . . + Horse-nettle . . . . . . . . . . . . . Solanum carolinense L . . . . . . . . . Solanaceae . . . . . . . . . . + Horseweed . . . . . . . . . . . . . . Lepti_lon canadense (L.) Britten _ . . . . . . ._ . . . . . . . . . . . . Carduaceae . . . . . . . . . . + Horseweed, Purple . . . . . . . L. divaricatum (M1chx.) Raf. . . . “ . . . . . . . . . . . . . + Hymenopappus, Smooth Hymenoppapus corymbosus HWhite. w n T. & G . . . . . . . . . . . . . . . . . . .. “ . . . . . . . . . . . .. + ymenopappus, oo y White . . . . . . . . . . . . . . . . H. tenuifolius Pursh . . . . . . . . . . “ . . . . . . . . . . . . . + Ibervillea . . . . . . . . . . . . . . . Ibervillea tenuisecta (A. Gray) Small. . . . . . . . . ._ . . . . . . . . . Cucurbitaceae . . . . . . . . — Indigo-plant, Lindheimer.. Indlgofera llndhelmcrlana Scheele . . . . . . . . . . . . . . . . . . . . F abaceae . . . . . . . . . . . . + Indigo-plant, Western. . . . I. leptosepala Nutt . . . . . . . . . . . . “ + Ironweed, Ta l . . . . . . . . . . . Vernonia maxima Small . . . . . . . + Isocoma, Drummond. . . . . Isocoma drummondii (T. & G.) Greene . . . . . . . . . . . . . . . . . . . . + Jimson-weed . . . . . . . . . . . . Datura stramonium L. . .. . . . . . . + Jimson-weed, PurpleT. . . . D. talula L . . . . . . . . . . . . . . . . . . . + Krameria . . . . . . . . . . . . . . . Krameria secundiflora DC . . . . . . —— Krameria, Hoary . . . . . . . . K. canescens A. Gray. . . .. . . . . . — Krameria, Small-leaved . . . K. parvifolia Benth . . . . . . . . . . . _ — Lambs-quarters . . . . . . . . . . Chenopodium album L . . . . . . . . . Chenopodlaceae . . . . . . . + Larkspur, Carolina . . . . . . . Delphinium carolinianum Walt. Ranunculaceae . . . . . . . —— Larkspur, hite . . . . . . . . . D. albescens Rydb . . . . . . . . . . . . . _ “ _ . . . . . . . . . . . . . — Lettuce, Grass-leaved. . . . . Lactuca graminifolia Michx. . . . . Clchoriaceae . . . . . . . . . . + Lettuce, Hairy . . . . . . . . . . L. hirsuta Muhl . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Lettuce, Prickly . . . . . . . . . L. virosa L . . . . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Lettuce, Western . . . . . . . . L. ludoviciana (Nutt.) DC . . . . . . “ . . . . . . . . . . . . . + Lions-heart, Slender. . . . . . Physostegia intermedia (Nutt.) _ _ A. Gray . . . . . . . . . . . . . . . . . . . Lamzaceae . . . . . . . . . . . —- Loosestrife, Narrow- Lythrum Iinearifolium leaved. _ (A. Gray) Small . . . . . . . . . . . . Lythraceae . . . . . . . . . . . + Lygodesmia, Texas . . . . . . . Lygodesmia texana (T. & G.) _ _ Greene . . . . . . . . . . . . . . . . . . . . Clchormceae . . . . . . . . . . + Malachra, Yellow . . . . . . . . M alachra capitata L . . . . . . . . . . . Malvaceae . . . . . . . . . . . + Mallow, Bristly-fruited. . . Modiola caroliniana (L.) y G. Don . . . . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Mallow, Common . . . . . . . . Malva rotundifolia L. . . . . . . . . . . “ . . . . . . . . . . . . . + Mallow, High . . . . . . . . . . . . M. sylveslris L . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + M l_ow, Small-flowered. . . M. purviflpra L . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Marilaunidium, Bristly. . . Marilaumdzum hispidum _ (A. Gray) Kuntze . . . . . . . . . . Hydroleaceae . . . . . . . . . —— Marshallla, Large- Marshallia grandiflora flowered. Beadle & Boynton . . . . . . . . . . Carduaceae . . . . . . . . . . + Marshallia, Narrow- leaved . . . . . . . . . . . . . . . . M’. caespitosa Nutt . . . . . . . . . . . . “ . . . . . . . . . . . . . + Medic, Black . . . . . . . . . . . . Medicago lupulina L . . . . . . . . . . . Fabaceae . . . . . . . . . . . . + Melampodium, Branched. . Melampodium ramosissimum . DC . . . . . . . . . . . . . . . . . . . . . . . Carduacepe . . . . . . . . . . + Mercury, Arc-shaped. . . . . Acalypha radians Torr. . . . . . . . . Euphorbzaceae . . . . . . . . + Mercury, Hornbeam . . . . . . A. ostryaefolia Ridd . . . . . . . . . . “ . . . . . . . . . . . . . + Mercury, Ivyleaf......... A.hederaceaTorr............... _“ . . . . . . . . . . . .. + Mesquite, Prairie . . . . . . . . Prosopis glandulosa Torr . . . . . . . M zmosaceae . . . . . . . . . . + Milkvetch, Carolina . . . . . . Aslmgalus carolinianus L . . . . . . Fabaceae . . . . . . . . . . . . + Milkvetch, Nuttall . . . . . . . H amosa nuttalliana (DC.) Rydb “ . . . . . . . . . . . . . + *Including a large number of non-cultivated species, such as Johnson Grass and various other introduced and native species. 28 BULLETIN NO. 398, TEXAS AGRICULTURAL EXPERIMENT STATION Table 3.——Relative Susceptibility of Non-cultivated Plants to Root Rot-Jlontniecl _ _ Relative Common Name Species or Botanical Name Family slijflllfipti- - i ity Milkvetch, Wright . . . . . . . Astra alus wrightii A. Gray. . . . Fabaceae . . . . . . . . . . . + Milkvetch, Wrinkled. . . . . A. re exus T_. &_G . . . . . . . . . . . . “ . . . . . . . . . . . . . — Milkweed, Broad-leaved. . Asclepias latifoIia_(Torr.) Raf“ . Asclepiadaceae . . . . . . . + Milkweed, Oblong-leaved.. Asclepzodora viridis (Wa t.) _ A. Gray . . . . . . . . . . . . . . . . . . . “ _ _ . . . . . . . . . . _ + Milkweed, Spreading. . . . . A. deciim ens_ (Nutt.) A. Gray.. “ . . . . . . . . . . . . . + Milkweed, Variegated. . . . Asclepias vqrlegatoi L . . . . . . . . . . “ _ . . . . . . . . . . . . + Monarda, Hairy . . . . . . . . . Monardq hzrsutisszma Small. . . . Lamiaceae . . . . . . . . . . . — Monarda, Slender . . . . . . . . M. tenuiaristala (A. Gray) _ Small ._ . . . . . . . . . . . .._ . . . . . . . “ , . . . . . . . . . . . . + Monoxalis. . . . . . . . . . . . . . Monoxalis dichondraefolia ~ _ (A. Gray) Small . . . . . . . . . . . . Oxalidaceae . . . . . . . . . . — Morning-glory, Long- _ _ leayed . . . . . . . . . . . . . . . . Ipomoea longlfolia Benth . . . . . . . Convolvulaceae. . . . . . . . + Morning- loijy, Small- flowere Pink . . . . . . . . . . I. caroliniana Pursh . . . . . . . . . . . “ . . . . . . . . . . . . . + Morning-glory, Small- ribbe . . . . . . . . . ._ . . . . . . I. cosfellata Torr . . . . . . . . . . . . . . “ _ . . . . . . . . . . . . + Morning-glory, White- flowered . . . . . . . . . . . . . . I. lacunosa_ L . . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Museniopsis . . . . . . . . . . . .. Museniopsis iexana (A. Gray) _ Coult. Rose . . . . . . . . . . . . .. Ammiaceae . . . . . . . . . . + Nemastylis, Northern. . . . Nemastylisocuta (Bart) Herb.. Ixiaceae . . . . . . . . . . . . . — Nightshade, Black . . . . . . . Solarium mgrum L . . . . . . . . . . . . Solanaceae _ . . . . . . . . . . + Nightshade, Silver-leaved. S. elaeagnifolium Cav . . . . . . . . . . “ _ . . . . . . . . . . . . + Orache, Halberd-leaved. . . Atriplex hastafa L . . . . . . . . . . . . . Chenopodiaceae . . . . . . . + Orache, Prickly . . . . . . . . . . A. acanthocarpa (Torr) S. Wats. “ . . . . . . . . . . . . . —l— Palmetto, Saw . . . . . . . . . . . Serenoa serrulata (Michx.) o0 . . . . . . . . . . . . . . . . . . . . . . Arecaceae . . . . . . . . . . . . — Parosela, Feathery . . . . . . . Parosela pogonathera Gray) Vail. . ._ . . . . . . . . . . Fabaceae . . . . . . . . . . . . + Parosela, Golden . . . . . . . . . P. aurea (Nutt.) Britton . . . . . . “ . . . . . . . . . . . . . + Parosela, Graceful . . . . . . . P. formosa (Torr.) Vail . . . . . . . . “ . . . . . . . . . . . . . + Parosela, Pink . . . . . . . . . . . P. dalea (L.) Britten . . . . . . . . . . “ . . . . . . . . . . . . . + Parsley, Sand . . . . . . . . . . . . Ammoselinum pope! & G. Ammiaceae . . . . . . . . . . + Par-snip, Cow . . . . . . . . . . . . Heracleum lanatum Michx . . . . . . “ . . . . . . . . . . . . . + Parthenium, Ragweed. . . . Partheniuin hysterpphorus L.. . . Carduaceae . . . . . . . . . . + Pea, Partridge . . . . . . . . . . . Chamaecrzsla fasciculata _ (Michx.) Greene . . . . . . . . . . . Cassiaceae . . . . . . . . . . . + Pea, Sensitive . . . . . . . . . . . C. procumbens (L.) Greene. . . . . “. . . . . . . . . . . . . + PeaYine, Leavenworth. - - . Vicia leavenworthii T. & G.. . . . Fabaceae . . . . . . . . . . . . . + Pectis . . . . . . . . . . . . . . . . . . Pectis tenella DC . . . . . . . . . . . . . . Carduaceae. . . . . . . . . . + Pennywort, Water . . . . . . . Hydrocotyle prolzfera Kellogg. . . Ammiaceae . . . . . . . . . . + Pepper-grass, Medium. . . . . Lepidium medium Greene . . . . . Brassicaceae . . . . . . . . . —— Peppergrass, Tall . . . . . . . . L. virgimcum L . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . — Peppergrass, Wild . . . . . . . . L. apetalum Willd . . . . . . . . . . . . . “ . . . . . . . . . . . . . ——— Persicaria, Mexican. . ._ . . . Persicaria mexicana Small . . . . . . Polygonaceae . . . . . . . . . — Persicaria, Pennsylvania. . P. pennsylvanica__(L.) Small. . .. “ . . . . . . . . . . . . . -— Phacelia, Bicknell . . . . . . . . Phacelia bicknellu Small . . . . . . . Hydroleaceae . . . . . . . . . — Phacelia, Crowded . . . . . . . P. congesta Hook. . . . . . . . . . . . . . “ . . . . . . . . . . . . . —— Phacelia, Dissected . . . . . . . P. dissecta (A. Gray) Small. . . . “ . . . . . . . . . . . . . —- Phlox, Rough . . . . . . . . . . . . Phlox aspera E. Nelson. . . . . . . . Polemoriiaceae . . . . . . . . -- Phyllanthus, Angled . . . . . . Phyllanthus polygonozdes Nutt. Euphorbiaceae . . . . . . . . + Phyllanthus, Carolina. . . . P. carolinensis Walt . . . . . . . . . . . “ . . . . . . . . . . . . . + Phyllanthus, Winged. . . . . P. avicularia Small . . . . . . . . . . . “ . . . . . . . . . . . . . + Pigweed, Winged . . . . . . . . Cycloloma atriplicifolium _ (Spreng.) Coult . . . . . . . . . . . . . Chenopodiaceae . . . . . . . + Plantago, Rough . . . . . . . . . Plantago inflexa Morris . . . . . . . . Planlaginaceae . . . . . . . —— Plantago, Western . . . . . . . P. occidentqlis Decne . . . . . . . . . . “ . . . . . . . . . . . . . — Plantago, Woolly . . . . . . . . Rslamfiifolia (Coult. & Fish.) ma . . . . . . . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . — Polypteris, Rough . . . . . . . . Polypteris callosa (Nutt.) _ . Gray . . . . . . . . . . . . . . . . . . . Carduaceae . . . . . . . . . . + Polypteris, Texas . . . . . . .. P. iexana (DC.) A. Gray. . . .. . “ . . . . . . . . . . . . . + Poppymallow, Clustered. . Callirrhoe triangulata _ (Leavenw.) A. Gray . . . . . . . . Malvaceac . . . . . . . . . . . + Pop pymallow, Fringed. . . . C. digitata Nutt . . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Poppymallow, Low . . . . . .. C. irwolucrata (Nutt.) A. Gray.. “ . . . . . . . . . . . . . + Poppymallow, Narrow- C. lineariloba (T. & G.) lo e . A. Gray . . . . . . . . . . . . . . . . . .. “ . . . . . . . . . . . .. + PoppymallowJPalm- eaved . . . . . . . . . . . . . . .. C. pedata A. Gray . . . . . . . . . . .. ‘ . . . . . . . . . . . .. + PLANTSSUSCEPTIBLE OR RESISTANT TO COTTON ROOT ROT 29 Table 3.'—'R6l3tlV6 Susceptibility of Non-cultivated Plants to Root Rot-Cont inred _ Relative Common Name Species or Botanical Name Family Siisclzetpti- i i y Portulaca, Hairy . . . . . . . . . Portulaca pilpsa L. . . . . . . . . . . Porlqlacaceae . . . . . . . . . + Potato, Hog . . . . . . . . . . . . . Hoflmanseggia denslflora Benth. Casszaceae . . . . . . . . . . . + Prairie-clover, Small- Pelaloslemon microphyllus leaved, T. G . . . . . . . . . . . . . . . . . . . . Fabaceae . . . . . . . . . . . . + Prairie-cloyer, White. . . . . P. albidus (T. & G.) Small. . . . . “ . . . . . . . . . . . . . + Prairiegentian, Slender. . . . Primrose . . . . . . . . . . . . . . . . Primrose, Oblong-leaved. . Prionopsis . . . . . . . . . . . . . . . Pussy-foot, Yellow . . . . . . . Ragweed, Common . . . . . . . Ra eed, Giant; loodweed . . . . . . . . . . . . Ragweed, Great . . . . . . . . . Ragweed, Lance-l_eaved . . . Ragweed, Perennial. . . . . . Ragwort, Prairie . . . . . . . . . Ruellia, Hairy . . . . . . . . . . . Ruellia, Stalked . . . . . . . . . . Ruellia, Tuberous . . . . . . . . Sage, Lance-leaved . . . . . . . Sage, Roemer . . . . . . . . . . . Sheepsorrel . . . . . . . . . . . . . . Sida, Heller . . . . . . . . . . . Sida, Long-beaked. . . . . . Sida, Narrow-leaved . . . . . . Sida, Prickl . . . . . . . . . . . . Sida, Rhom oid-leaved. . . Sida, Round-leaved . . . . . . Sida, Texas . . . . . . . . . . . . . Sida, Triangular . . . . . . . . . Sideranthus . . . . . . . . . . . . . Sideranthus, Viscid. . . . . . . Skunkcabbage. . . . . .. . . . Snailseed, CarolinaT . . . . . . Sneezeweed Sneezeweed, Small- flowered Solanum, Spiny . . . . . . . . . . Sow-thistle, Spiny . . . . . . . . Spermolepsis . . . . . . . . . . . . Spurge, Hairy . . . . . . . . . . . Spurge, Round-leaved. . . . Spurge, Toothed . . . . . . . . . Spurge, Upright Spotted . . St. Johnswort, Spotted. . . . Storksbill, Texas . . . . . . . . . Sunflower, Hairy. . .. . . . . . Sunflower, Hoary . . . . . . . . Sunflower, PrairieT . . . . . . . Sunflower, Threadleaf. . . . Talinum, Golden . . . . . . . . . Tetraneuris, Fine-leaved. . Tetraneuris, Narrow- aved . Thamnosma, Texas . . . . . . Thistle, Bull . . . . . . . . . . . . . Thistle, Russian . . . . . . . . . Thistle, Slender . . . . . . . . . . Tievine, Common. . . . . . .. Tragia, Branching . . . . . . . Tragia, Catnip . . . . . . . . . . . Tragia, Prickly . . . . . . . . . . Trumpetweed. . . . . ifgaihyema foetida (L. Eustoma gracile Enge‘m. . . . . Galpinsia harlwegii (Benth.) Britton . . . . . . . . . . . . . . . . . . . . G. interior Small . . . . . . . . . . . . . . Prionopsis ciliafa Nutt. . . . . . Petalostemon abovatus T. & G.. . Ambrosia arfemisiifolia L . . . . . . A. aptera DC . . . . . . . . . . . . . . . . . A. Irifida L . . . . . . . . . . . . . . . . . . . A. biafentala L . . . . . . . . . . . . . . . . A. psilosfachya DC.. .. . Senecio plattensis NiitL. Ruellia ciliosa Pursh . . . . . . . . . . R. pedunculata Torr . . . . . . . . . . . R. tuberosa L . . . . . . . . . . . . . . . . . Salvia lanceolata Willd . . . . . . . . . S. roemeriana Scheele . . . . . . . . . Rumex acetosella L . . . . . . . . . . . . , gida helleri Rose . . . . . . . . . . . . . . . longipes A. Gray . . . . . . . . . . . . anguslifolia Lam.. . . . . . . . .. . spinosa L . . . . . . . . . . . . . . . . . . .rh0mbif0liaL............... . hederacea Torr . . . . . . . . . . . . . . Jexana (T. & G.) Small. . . . . S. hastata S. Hil . . . . . . . . . . . . . . Sideranthus colula Small . . . . . . . S. rubiginosus (T. & G.) -Britton . . . . . . . . . . . . . . . . . . . Raf.. . . . ballia carolina (L.) ritton. . . Helemum microcephalum DC.. . H. parviflorum Nutt . . . . . . . . . . . Solanum aculeaiissimum Jacq.. . Sonchus asper (L.) All . . . . . . . . . Spermolepsis echinatus (Nutt.) Heller . . . . . . . . . . . . . . Chamaesyce malaca Small . . . . . . C. serpens (HBK.) Small. . . . . . Poinsettia dentala (Michx.) Small Chamaesyce nutans (Lag) Small Hypericum maculatum Walt. . . . Erodium texanum A. Gray. . . . . Helianthus hirsutus Raf. . . . . . . H. cinereus_ T. & G . . . . . . . . . . . . H. petiolaris Nutt . . . . . . . . . . . . . H. filiformis Small . . . . . . . . . . . . Talinum aurantiacum Engelm. . Tetraneuris Iinearifolia (Hook.) Greene . . . . . . . . . . . . . . . - - - - . . . . . - . . . . - . . . T. linearis (Nutt) Greene. Thamnosma texana (A. Gray) Torr . . . . . . . . . . . . . . . . . . . . . . Carduus Ianceolatus L . . . . . . . . . . Salsola pestifer A. Nelson . . . . . . Carduus austrinus Small . . . . . . . Ipomoea frifida (HBK.) G. Don . . . . . . . . . . . . . . . . . . . Tragia ramosa Torr.. . . . . . . . . . T. nepetaefolia Cav. . . . . . . . . . . . T. urticacfolia Michx . . . . . . . . . . Eupatorium compositifolium Walt . Geniianaceae . . . . . . . . . Ep ifiobiaceae . . . . . . . . . . C arduaceae . . . . . . . . . . Fabaceagz . . . . . . . . . . . . Ambroszaceae . . . . . . . . . I Carduaceae . . . . . . . . . . Acanthaceae. . . . . . . . .. (i u Polygonaceae . . . . . . . . . M aguaceae . . . . . . . . . . . Carduaceae . . . . . . . . . . u Aracgae . . . . . . . . . . . . . Memspermaceae . . . . . . Cardizaceae . . . . . . . . . . Sqlanapeae . . . . . . . . . . . C ichoriaceae . . . . . . . . . . Ammiaceae . . . . . . . . . . Euphorbiaceae . . . . . . . . (I Hyperjcaceae . . . . . . . . . Geramaceae . . . . . . . . . . Carduaceae . . . . . . . . . . . 6S (l Portulacaceae . . . . . . . . . Carduaceae . . . . . . . . . . Rutaceae . . . . . . . . . . . . . Cardiiaceae . . . . . . . . . . . Chenopodiaceae . . . . . . . Carduaceae . . . . . . . . . . C onvolvulaceae . . . . . . . . Eaphorbzaceae . . . . . . . . C arduaceae . . . . . . . . . . + ++++ ++++ + + l++++l1++ +++ +++ ++++ +++++++++llI++|+++++ +++|I 30 BULLETIN NO. 393, TEXAS AGRICULTURAL EXPERIMENT STATION Table 3.——Relative Susceptibility of Non-cultivated Plants to Root Rot—C0ntinucd _ _ _ Relative . Common Name Species or Botanical Name Family Suscepti- ~ bility Tumbleweed. . . . ._ . . . . . . . Amgzranthus albus L . . . . . . . . . . . Amaranthaceae. . . . . . . + Umbrellawort, Hairy. . . . . Allzonia pllosa (NutL) Rydb. . . Allioniaceae . . . . . . . . . . + Umbrellawort, Lance- shaped . . . . . . . . . . . . . . . . A. lanqeolata Rydb. . . . . . . . . . . . “ . . . . . . . . . . . . . + Umbrellawort, Smooth. . . . A. florzbunda (Cho1s.) Rydb. . . “ . . . . . . . . . . . . . + Umbrellawort, Sticky. . . . . A. comata Small . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Umbrellawort, Texas. . . . . A. tergqnsis (CoulL) Small . . . . . . “ . . . . . . . . . . . . . + Velvetleaf . . . . . . . . . . . . . .. Abutilion abutilon (L.) Busby. . Maluaceae . . . . . . . . . .. + Verbena, New Mexican . . . Verbena neo-mexicana (A. Gray Small . . . . . . . . . . . . Verbenaceae . . . . . . . . . . —— Verbena, Small-flowered.. . V. ambrosi ol_ia Rydb.. . . . . . . . . “ —— Vetch, Louisiana . . . . . . . . . Vicia ludqviczana Nutt . . . . . . . . + Vetch, Narrowleaf . . . . . . . V. angustifolia L . . . . . . . . . . . . . . + Vetch, Small-flowered. . . . V. micrantha N utt . . . . . . . . . . . . + Vetch, Texas . . . . . . . . . . . . V. tezcana (T. & G.) Small. . . . . + Vetch, Wild . . . . . . . . . . . . . V. reverchonii Wats . . . . . . . . . + Waterhemp, Southern. . . . Acmda australis A. Gray . . . . . . + Waterhemp, Whitish. . . . . A. cannabina . . . . . . . . . . . . . . . + Wildbergamot. . . ._ . . . . . . . Monarda fistulosa L . . . . . . . . . . . — Wildbergamot, Hairy.. . . . M. molljs L. . . . ._ . . . . . . . . . . . — Woodsorrel, Berlandier. . . Lotoxalzs berlandzeri (Torn) _ Small . . . . . . . . . . . . . . . . . . . . . Oxalidaceae . . . . . . . . . . Woodsorrel, Drummond. . Ionoxalis drummondii (A.Gra_y) Rose..._..._ . . . . .. “ .. . . . . . . . . . .. —-— Wormseed . . . . . . . . . . . . . . Chenopodium anthelmintlcum L. Chenopodiaceae . . . . . . . + Wormwood, Mexican. . . . . Artemisia mexicana Will . . . . . . Carduaceae . . . . . . . . . . . + Wormwood, Western. . . . . A. gnaphalodes N utt . . . . . . . . . . . “ . . . . . . . . . . . . . + Yellow-flax, Fluted . . . . . . . Cathartolinum sulcatum _ _ (Ridd.) Small . . . . . . . . . . . . . . Lmaceae . . . . . . . . . . . . . + Yellow-flax, Prairie . . . . . . . C. rupestre (Engelm.) Small. .. . “ . . . . . . . . . . . . . + Yellow-flax, Winged... . . . C. alaium Small . . . . . . . . . . . . . . “ . . . . . . . . . . . . . + Yucca, Prairie . . . . . . . . . . . Yucca conslricta Buckl. .. . . . . . . Dracaenaceae . . . . . . . . . —- Yucca, Twisted-leaved. .. . Y. rupicola Scheele . . . . . . . . . . . “ . . . . . . . . . . . . . — Zexmenia, Bristly . . . . . . . . Zexmenia hispida (HBK.) A. Gray . . . . . . . . . . . . . . . . . . . Carduaceae . . . . . . . . . . +