nr TT Toran a rE Pi nt ws =x Eo Biers fe a ATA SDE Tora Sow i a Be = 7 ah 7 es ? Bra AT ER Be PINT ou a Se 3 = Fens ed ee Ce Elli ree = anes lr Er Te Eons ahaa = = Svs rhe ‘ Lal = : iT Bra Bea Heads a at dr : : Yeas Ae 5 % 3 re LE Ze 5 : = ; UC BERKELEY MASTER NEGATIVE STORAGE NUMBER 00-121.3 (National version of master negative storage number: CU SN00121.3) MICROFILMED 2000 UNIVERSITY OF CALIFORNIA LIBRARY PHOTOGRAPHIC SERVICE USAIN State and Local Literature Preservation Project Funded in part by the National Endowment for the Humanities REPRODUCTION AVAILABLE THROUGH INTERLIBRARY LOAN OFFICE MAIN LIBRARY UNIVERSITY OF CALIFORNIA BERKELEY, CA 94720-6000 COPYRIGHT The copyright law of the United States (Title 17, United States Code) governs the making of photocopies or other reproductions of copyrighted materials including foreign works under certain conditions. In addition, the United States extends protection to foreign works by means of various international conventions, bilateral agreements, and proclamations. Under certain conditions specified in the law, libraries and archives are authorized to furnish a photocopy or other reproduction. One of these specified conditions is that the photocopy or reproduction is not to be "used for any purpose other than private study, scholarship, or research." If a user makes a request for, or later uses, a photocopy or reproduction for purposes in excess of “fair use," that user may be liable for copyright infringement. University of California at Berkeley reserves the right to refuse to accept a copying order if, in its judgment, fulfillment of the order would involve violation of copyright law. California. State Commission of Horticulture Destructive insects and their control, by O. E. Bremner, secretary, California state commission of horticulture. Sacramento, Calif., 1910 BIBLIOGRAPHIC RECORD TARGET University of California at Berkeley Library USAIN State and Local Literature Preservation Project Master negative storage number: 00-121.3 (national version of the master negative storage number: CU SN00121.3) FORMAT: BK LEVEL: r ISBN: GLADIS#: 33876472G LANG: eng CNTRY: cau LCCN: MOD: 990607/MO ME: California. State Commission of Horticulture. Tl: Destructive insects and their control, by O. E. Bremner, secretary California state commission of horticulture IM: Sacramento, W. W. Shannon, superintendent state printing, 1910 CO: 39 p., illus. (incl. diagrs.) 23 cm CALL: SB824.C2.A4 BIOS Microfilmed by University of California Library Photographic Service, Berkeley, CA FILMED AND PROCESSED BY LIBRARY PHOTOGRAPHIC SERVICE, UNIVERSITY OF CALIFORNIA, BERKELEY, 94720 DATE: 10/00 REDUCTION RATIO: 9 id PM-1 3%"x4” PHOTOGRAPHIC MICROCOPY TARGET NBS 1010a ANSI/ISO #2 EQUIVALENT Ee NR l= fl LZ his pee rm— == t 171910 CALIFORNIA STATE COMMISSION OF HORTICULTURE J. W. JEFFREY, Cédmissioner Rar DESTRUCTIVE INSECTS AND THEIR CONTROL or BY } 0. E. BREMNER Secretary California State Commission of Horticulture SACRAMENTO: W. W. SHANNON, : =: © : SUPERINTENDENT STATE PRINTING 1910 men wm rR, + L A - . i 3 # / g2 4 6 © y { } / y © g 97 n Pe 5 Ln ) JA ‘ 30 > > © 2 a ) pe ; 5 A ve A i . 4 h « 5 ¢ a { / et ) r . ° ) 8300 0 0906.8. 50 , Ce A AS 99 Q a 3 @ 1 9 - 9 > 3 i » : Qo . ) a = : 2 . 00% © I eo 0 2 0 5.0 / 2 ® 00 nO ’ 3 y 2 . > > s ya. 0 OB A ) / } 0 J ) ~ . of ( NM 7 IG / / ’ , / £1 Pbrary Ad K Y & [ DESTRUCTIVE INSECTS AND: THEIR CONTROL. Insect invaders, and we include in this category spiders and mites, levy, it is roughly estimated, a tax of ten per cent on all the products of our orchards and fields. It often happens in special seasons that - MAIN OFFICE: these attacks may even cause the total destruction of some one or all : of our crops in certain localities. It is, therefore, necessary to be pre- pared at all times to destroy or control these enemies, and with this end if CALIFORNIA STATE COMMISSION OF HORTICULTURE CarrrorL BUILDING, SACRAMENTO, CAL. J. W. JEFFREY, Commissioner. a ee aT Sacramento . . ays . > . i ©. BREMSER. & ; in view it is the purpose of this bulletin to present the latest remedies nl 5 ; yy BOROUITY = 2 ~ suwrnsnnnns srs rmnnimnun manson aspen tony Sacramento in the form of either natural or artificial means of control. It is i MISS A. G. BIRD, Clerk -- eve nema Ea TE ee Sacramento always necessary to determine the specific cause of the injury in order 4 : / 3; : : i GEORGE COMPERE, Special Field Agent... __._..____. (oH Sacrbrmento to combat the pest in the most effective manner. | X. J. BRANIGAN, Fiold Ayent ooo... aa For convenience insects are separated into two great divisions, those i Bi R-WELINEY. Zid vddont with biting and those with sucking mouth parts. The biting insects take : EF ’ . y € BIB cis i i a mh i ae aw 08 wea ar lab la : . . . . . § 4 GE re Sacramento portions of the plant directly into their stomachs by a process not unlike | 4 | our own eating habits, having two horny jaws, which, unlike ours, work QUARANTINE DIVISION: ; i 8 ~ gideways. They include such forms as grasshoppers, leaf-eating beetles, : I larvae of moths, and butterflies. The sucking insects on the other hand insert a sort of beak or pro- DUDLEY MOULTON, Deputy Commsssioner- o-oo oe eee San Prapoisio { | boseis into the tissues of the plant and extract therefrom the essential | : WILLIAM WOOD; Jrspeotor:s....coueesoneon iit iivieniten io Witte: juices. As examples of. these forms are the squash-bug and the scale H F. X. WILLIAMS. dssistunt J ht i families, plant lice, etc. While the first division may be successfully ; YIU, JIIDECUIT vv con aempureetupintlony s=teecey San Francisco | | fought by means of poisonous ingredients, which are placed on the food "either in liquid or dry form, and then taken into the system of the insect along with the portions of the plant, the second can only be | STATE INSECTARY: i treated by means of irritants, sprays, in dust or liquid form, that kill : | by contact, and also by poisonous gases that are taken into the body E. KE. CARNES, Superintonilent....... on cousiosansissiin i 2 0 Sabfamuiic | through the respiratory organs. As the rank and file of the fruit ne growers are not familiar with the nature of insects in particular, it is i Room 11, FErrY BuiLping, SAN Francisco. —_—— a 3 CariTor PARK, SACRAMENTO. i i Ra Supe ot 1 TYTN Sacramento always essential before applying & remedy to know just how the insect } Su Plater tures : i o, { should be fought, and therefore important to consult some authority if | MN adh ! there is any doubt as to the nature of the injury and the best means of | Ld fighting this special foe. Any insects to be determined should be sent i to the State Insectary, Sacramento, or to our Quarantine office, room 11, Ferry Building. These specimens should be sent in pasteboard or thin wooden boxes, and never in envelopes, as those sent in this way are always smashed until unrecognizable. We maintain at Sacramento a State Insectary, where we propagate and distribute beneficial insects which prey on those that are destructive 242702 . . . * .® . Seno ssa ° ° . . 3 - * AR] [EEN] seen 4 DESTRUCEIVE INSECTS AND ‘THEIR . CONTROL. ‘to our crops. While this department can not as yet furnish means of control for all our pests, it is well to keep in communication with it, as we are constantly receiving new supplies from practically all over the world. All beneficial insects, bulletins and information are furnished to growers free. Always send a small sample of insects inclosed in tight pasteboard box when applying for parasites unless you are sure what they are. ; . ¢ ° eo vet 3 ed ¢ oe % eee € ‘Spiders and Mites. On AeciAUuous LIees. .... covets renders samen Bryobia pratensis. On CIHITUS LTeBS. . oo cvs ass vn cdainannsinnrivie Tetranychus mytilaspidis. On hops and beans. ... ....c.covovvien vines ...Tetranychus bimaculatus. Red spiders are quite a common pest on deciduous trees, particularly prunes, almonds, cherries, apples, etc. The spider spends the winter in the egg form, which is a bright red, and is generally found around the buds. This hatches into a little spotted spider, which attacks particularly the under side of the leaves. The injury is made with a sharp, shovel-like mouth plate, which makes a flat cut in the leaf, and from this incision the spider. extracts the juices of the leaf. The leaves turn yellow in these spots, and, finally, if the attack is severe, drop. It is partial to hot, dry weather, and often much dam- age is done by the burning of the fruit and young growth after the defoliation. The injury to citrus trees, hops, beans and hothouse plants (particularly carna- Fig. 1.-Six-spottc a mite (T. seomac: tions) is of practically the same nature, Ig A AE ee with the exception that the greater por- all much enlarged. tion of the damage in these cases is due to the extraction of nourishment from the plant. The eggs of the spiders (7. bimaculatus) on hops and beans are colorless, the spiders also being less conspicuous than those containing more color. These also spin a fine web over the surface of the leaf, where the attack is made, making the application of sprays more difficult. 7. mytilaspidis on citrus trees has eggs distinctive and easily recognized. They are laid singly on the leaf and on the upper side of each is a small stalk from the end of which silken threads extend to the leaf, thus securing the egg firmly in place. The most used and simplest remedy is sublimed sulphur, applied with a power blower. This sulphuring must be repeated every two or three DESTRUCTIVE INSECTS AND THEIR CONTROL. o weeks in moderate weather, and every few days in hot weather. This is on account of the rapid action of heat on sulphur and the rapid increase of spiders in hot weather. Of the liquid sprays, lime-sulphur wash, when applied thoroughly, is very effective for this purpose. Use the regular formula, as follows: HIE ii srinivas ead sin ans suk in mareiine ess wes, 33 pounds. BHIBIUE cvs tin sir invess san rnssnbasntinenscnrsuvels 66 pounds. TTT ier sane Ce a a re Ea a de Se a We es 200 gallons. To prepare, slake the lime with warm water enough to do it thoroughly and during the process add the sulphur. Boil for one hour or longer with just water enough to prevent burning (50 gallons), and if it then forms a deep, amber-colored liquid, it is done, and warm water may be added to reduce to spraying strength. It works better warm than cold although it is not more effective. One of the best formulas is the lye- sulphur. Concentratel 1ye......ccoeiiirrenrsrrsnrttecracenscsnsens 10 pounds. SUIPHUT «oc civoestrstrtrensnsesstrsntstssssnnesssnsenss 20 pounds. Mix the sulphur into a thin paste with cold water and then add the lye. Keep constantly stirring and adding water from time to time to prevent burning. This will, when finished, make a stock solution of 20 gallons. Use two gallons of this to 50 gallons of water. A winter application on deciduous trees of the lye-sulphur wash or kerosene emulsion (1 to 10) is highly advisable. The dry sulphur is best for use on citrus trees or tender plants while the sprays give better results on deciduous trees, hops, beans, etc., when it is possible to spray advantageously. Always apply the dry sulphur in the early morning (3 to 10 a. m.), with a power blower preferably, although a seed sower, either hand or attached to a wagon, can be arranged so as to work nicely by attaching a funnel, and gearing very high. One essential step in the control of red spiders on hops, beans, and greenhouse plants, is clean cultivation,—the destruction of all plants harboring the pest during the winter must be strictly attended to. Eriophyes pyri, E. vitis, and E. oleivorus. The blister mites, or Phytopti, are minute, semi-transparent four- legged members of the spider family. They attack grapes, walnuts, pears, and many other trees and plants, forming blister-like excretions on the surface of the leaves. The mites really attack the hairs on the under surface, causing them to take on an abnormal growth, which causes a distortion of the leaf. These patches are at first white, but afterwards turn brown. In the worst cases (as in the case of grapes), the whole under surface of the leaf may take on this color. These affected leaves drop prematurely, causing a check to the vine and sun- a TR - Sri es fo IF wr ST LE a i i & k it 1 a ————— 6 DESTRUCTIVE INSECTS AND THEIR CONTROL. burn and loss of saccharine matter to the grapes. The mites winter over or hibernate around the dormant buds in the long plant hairs always found there. It is possible to reach them very effectively by a winter spray of kerosene emulsion or lye-sulphur spray, as given for red spiders. In the early spring when they first make their appearance on the leaves, use the dry sulphur treatment. The winter spray is the most effective, and can be applied practically at any time during the dormant period of the tree or vine. Russet mite of orange and silver mite of lemon (E. oletvorus), so called because of its injury to these fruits, while similar to these other mites in form, is different in habits and effect on the plant. It attacks the stems, leaves, and fruit. The stems and leaves lose their green color and take on the appearance of being varnished. The oranges scab over and are called russets on account of their color. Fi1G. 2.—Pear-leaf Blister Mite (E pyri). Greatly In case of the lemons, they change to a silver gray, from whence the name, silver mites. This injury is caused by the breaking down of the oil cells in the epidermal tissues of these fruits. This mite is successfully fought by the application of sulphur in its purest and finest state. The resublimed flowers applied with a power blower gives the best results. At present this pest is con- fined to a small area (one county) in California, and care should be - used to prevent its introduction into other sections. Peach Twig-borer, or Peach Moth (Anarsia lineatella). It is a common sight to see the young stems withering and dying, particularly on our young peach trees. Upon examination we either find a small worm in the center of the twig, boring its way from the bud toward the limb or the empty gallery it has made. This twig-borer passes the winter in a tiny cocoon generally in the crotches of the limbs. This minute little worm begins to work out of its winter quarters about ten days previous to the time of blossoming, and attacks the young, growing buds. After destroying these and reaching maturity it spins a cocoon under the loose bark, where it passes its quiescent or pupal state, and comes out as a tiny moth, which lays its eggs on the twigs. This egg hatches into a worm, which bores into the twigs, and later also the fruit. The third generation lays its eggs on the fruit and attacks this portion only. The only time this insect can be successfully fought is while in its winter state, or rather just as it is leaving its winter cocoon. Use the lime-sulphur solution as given for spiders and mites; or a spray DESTRUCTIVE INSECTS AND THEIR CONTROL. 7 of lime, sulphur and salt, applied just before the buds open in the spring, will give perfect success. CASIAEed HINe .... ci .vivtsariebervernsreriasrsonnsndnes 40 pounds. BUIIOr irs heres srs rr esa see ae 20 pounds. I SE de vei Ee dee a WE a a eis 15 pounds. WWRLET ..vuvuvv ir cnsersnsnrssvanansansirsasninnsnnass 60 gallons. Place 10 pounds of lime and 20 pounds of sulphur in a boiler with 20 oallons of water, and boil over a brisk fire for not less than one hour and a half, or until the sulphur is thoroughly dissolved. When this takes place, the mixture will be of an amber color. Next place in a cask 30 pounds of unslaked lime, pouring over it enough hot water to thoroughly slake it; and while it is boiling, add the 15 pounds of salt. When this is dissolved, add to the lime and sulphur in the boiler, and cook for half an hour longer, when the necessary amount of water to make the 60 gallons should be added. Peach Root-borer (Sanninoidea opalescens). This insect works similar to the Eastern peach root-borer (S. exitiosa), and fortunately has only made its appearance in one district in Cali- fornia. Its attack is particularly harmful to prunes. Great care should be exercised to not introduce this or the Eastern one on nursery stock. It is readily noted by the exudation of gum on the roots or crown of the tree. The most successful treatment has been digging out the borers with a gouge in the fall of the year, and painting the crown of the tree the first of March, after scraping away dirt to a depth of 6 inches below the surface, with the following wash composed of quicklime and crude oil, 16° Baumé: Slake 50 pounds of lime and while slaking pour in 3 callons of crude oil, work into a thick whitewash. The Corn Worm (Heliothus armiger). The appearance of this pest is too well known to require any comment. The housewife may have sound corn for her table if the gardener exer- cises proper care, or, rather, if all the cardeners exercise this care in destroying the pest. The eggs are laid by the moth on the corn silk. The larva, hatching, crawls to the young ear and begins eating. When full grown it leaves the ear and pupates in the soft ground. A trap can be used for the adult moth consisting of molasses poisoned with arsenate of lead or Paris green, placed in the garden in shallow tin cans on sticks. But the best way is to raise a trap crop of very early corn and as soon as this has become infested, remove and feed to the stock. Our common ladybug, H. convergens (red with black spots), is a voracious feeder on the moth eggs. rn rns A ARIE ce AA SS Ee Tem A aes tt RE DESTRUCTIVE INSECTS AND THEIR CONTROL. The Brown Day Moth (Pseudohazis eglanterina). The larva of this moth has caused a great amount of damage to prunes and cherries during the past few years, and in some cases spraying with arsenate of lead, 1 pound to 25 gallons of water, should be resorted to; but, generally speaking, it is so well controlled by native parasites that no artificial means need be used to control it. An internal egg, and a larval parasite, are particu- larly active. Fic. 3.—Brown Day Moth Cater- Silat (P. eglanterina), parasitized. ourtesy U. 8S. Dept. Agr. °° Fic. 4.—Brown Day Moth (P. eglanterina). Eggs and young larvee. Courtesy U. 8. Dept. Agr. Cankerworm (Alsophila pometaria). The cankerworm, or measuring worm, is often a very serious pest in our prune and apple orchards. The adult female is a wingless moth emerging from the ground from the middle of October until the early part of January. It crawls up the trees just after the fall rain and deposits its eggs in masses around the small twigs. The young hatching from these eggs just at the time the new leaves put out in the spring does serious damage, sometimes completely defoliating and destroying DESTRUCTIVE INSECTS AND THEIR CONTROL. 9 not only the crop for that season, but checking the trees so that the next year’s crop will be also affected. Practically, the only means of control is trapping or preventing the females from climbing the trees. This has been best accomplished by a preparation known as tree tanglefoot obtainable from the company that manufactures the tanglefoot fly paper. This can be applied directly to the bark of the tree, but seems to give better results when put on the prepared paper. This should be applied to the trees in the fall (October 15th) before any moths have made their appearance, and should be watched if the moths are very numerous, so that they may not bridge the sticky band. The Cabbage-worm (Pontia rape). This and others of the same but- terfly family (Colias), may be con- trolled by a spray of tobacco extract (1 to 50) in small gardens, but for alfalfa fields and large garden patches, it is advisable to apply to the State Insectary for the very efficient parasite (7Teromalus pu- parm). : Fic. 5.—Cabbage-worm (P. rapa), larva and adult. Tent-caterpillar (Malacosoma disstria). These leaf-eating caterpillars have been quite abundant and injurious to our prunes and apples for the past few years. The eggs are laid by brownish moths, with a conspicuous band across the fore wings, in the early summer. These eggs are deposited in clusters around the outer twigs of the trees, and in the following spring hatch into hairy cater- pillars, which destroy the leaves first near where the eggs are laid and gradually extend to the other limbs. They form a web or nest on the branch where they start working, and all return and cluster in this nest when not feeding. There is an exception to this habit, however. One of our California species, M. disstria, does not form a web, but clusters on the trunk or larger branches. Care should be taken to cut oft and destroy these clusters of eggs while pruning the trees in the winter. As soon as the nests are formed they should be cut out and burned. Torches are often used to burn the masses of caterpillars when they congregate on the branches and trunks of the trees. There is a tachina fly parasite which lays its eggs preferably upon the head of the cater- pillar. . The young grub from this egg feeds on the interior of the cater- pillar. Parasitized caterpillars are readily recognized from their gaunt = PPL TTT, 10 DESTRUCTIVE INSECTS AND THEIR CONTROL. appearance and slow movements, being almost lifeless. Also when pressed between the thumb and finger the impression remains. Many growers are careless with the prunings from the trees, dumping them in fence corners or along ravines. This brush should always be burned. Tussock-moths (Hemerocampa vetusta). The depredations of this moth are similar to the tent-caterpillars, excepting that they feed separately and also attack the fruits. It attacks particularly the apple and the live oak. The eggs are laid on the trunks and larger limbs in white masses by the female moth, which | is practically is but one brood a year, the eggs of which are laid in June, not hatching until the following March. These caterpillars are perhaps the hardest of any to control as they are prac- A tically resistant & to any poisonous spray, and their F1G. 6.—Tussock-moth (H. vetusta). a, female moth; b, young cata- habits are such pillar; ¢, female pupa; d, male pupa; e, larva on leaf; f, male moth. as to leave mo vulnerable point. The females pass the resting stage spun up in silken cocoons in crevices of the bark or large limbs and the only way to reach them in this stage is by hand-picking. When the attack by the young caterpillars becomes evident, if the trees are violently jarred and a barrier placed around the trunk of the tree to prevent them crawling up, a large percentage may be destroyed. These barriers are made of steep earth mounds or sticky bands, the best of which is the tanglefoot, used for cankerworm and applied in the same manner. There are several beneficial insects which are very helpful in keeping this insect in check. A hymenopterous egg parasite is particularly useful. The fact that the inroads of this insect are very sporadic shows that the parasite plays a great part in its history. wingless. There DESTRUCTIVE INSECTS AND THEIR CONTROL. 11 Red Hump Caterpillar (Schizura concinna). The red hump caterpillar is quite similar in its feeding habits to the tent-caterpillars, confining itself to one section of the tree until defo- liated. The caterpillar is of a reddish color with yellow and white ‘stripes. It has a conspicuous red hump on the fourth segment on which are four black spines. It spins its cocoon among the fallen leaves. The adult moth is brownish gray. It emerges from its cocoon in the early spring. They may be very successfully fought by pruning off and destroying the limbs containing the caterpillars when they first make their appear- ance. Clean culture is also essential, as every moth destroyed in its cocoon means the destruction of a colony the following spring. Cut Worms (Noctuide). These night-flying moths are a constant source of annoyance and a great source of loss to gardeners and nurserymen, as well as the orchardist. The species are variable in their habits, the larva, the source of the damage, invariably secreting itself in the loose earth from one half to two inches deep, under clods or in grass roots. Some will climb peach trees and destroy the buds and young shoots. A’ case occurred recently where ten acres of grapevines with young shoots six inches long were completely eaten back to the old wood. Others stay close to the ground and destroy the leaves and stock of a great range of plants,—young citrus seedlings in the seed bed, cabbage plants, tomatces, peas, beans, ete. Mechanical means is the quickest way of “ridding a garden of this pest. Careful cultivation, removing weeds and clods where they can hide and destroying them as you hoe, the placing of traps, such as small pieces of board or making holes with the hoe handle about 6 inches deep, where they will hide and can be killed, are good methods of control. Make a thick paste of bran or flour 10 parts, Paris green 1 part, and add 2 parts molasses or glucose to retain the moisture. Place in small mounds where the insects can procure this poison bait. Poison alfalfa or cabbage leaves by spraying thoroughly with 1 pound of arsenate of lead to 15 gallons of water and place in small heaps where they appear. In the case of peach orchards or vineyards, thorough hoeing, and the destruction of the worms are the best methods. Grasshoppers (Acridide). These sporadic pests, while always with us, do not appear every season in such numbers as to become a serious menace. The destructive season usually occurs when we have had a scarcity of spring rains i PAA i A. — 12 DESTRUCTIVE INSECTS AND THEIR CONTROL. causing their native food in the uplands to become exhausted. They then descend on the grainfields, vineyards, and orchards, and take all before them. In some sections, where it is impracticable to plow the upland pasture regions, the surest method of destruction, and this includes practically all the grasshopper infested places, is the raising of great flocks of turkeys which feed entirely on the hoppers, being ‘herded much the same as sheep on these upland regions. ‘When the hoppers make their appearance, the best means of controlling them is by the use of poisonous baits or food, such as poisonous alfalfa, bran, ete., as given for cut worms. False Chinch-bugs (Nysius angustatus), Squash-bugs (Anarsa tristis), Harlequin Cabbage-bugs (Murgantia histrionica). These insects attack practically all varieties of fruit and vegetable crops. One species (N. angustatus) is very injurious to young orange trees, while others are very destructive to strawberries; but whatever they attack, the nature of the injury is just the same. They are provided with a stout, sharp beak or proboscis, which they insert into the plant tis- sues and draw out the sap. If you will turn one over on FiG. 7.—False Chinch-bug (N. angustatus). Fnlarged. lia hack, you will either Se this beak folded down, be- tween the front legs or sticking out straight. These insects all emit a very disagreeable odor when crushed, which serves to distinguish them from families similar in appearance. They have what we call incom- plete metamorphosis, in other words, no pupal, or resting stage. The young when it hatches, resembles the adult in every respect, with the exception of having no wings. These gradually form as the insects grow larger. On account of their feeding habits they are hard to combat. They readily succumb to kerosene emulsion spray . . Fi6. 8.—Harlequin Cabbage-bug (M. histri- in the young stages, but in the adult = onica). aandb, young; c,d, ande, eggs; are practically immune from this class dy sae. of remedies. They hibernate throughout the winter in the adult form in bunches of weeds or straw, piles of pickets, or neglected fence corners. It will thus be seen that clean, careful cultivation is essential. Clean up and keep clean every winter habitat. Put out piles of straw and when DESTRUCTIVE INSECTS AND THEIR CONTROL. 13 they collect, burn. In the very early spring plant a few hills of the food plants they seem to attack the most severely. They will collect on Fig. 9.—Successive instars of the Squash-bug (4. tristis). these and by destroying the trap crop you will often exterminate this hold over brood. Wire Worms (Elateride). These troublesome pests, while very common, are difficult to control. The larva, hard, tan-colored worms, with distinet joints, very often destroy seeds of the squash family as fast as planted. They are also found very destructive to beans and even corn. In fact, they will attack nearly every variety of garden crop. 2 os The adults are black or brown beetles, notable for their peculiar characteristics of springing into the air with a sharp click when placed on j their backs, Soot and salt have been used on the ground to advantage, but undoubtedly the 5. 10 _wire-worms; larva best is an application of tobacco dust which and adult. acts as a fertilizer and at the same time drives away the worms. Apply at the ratio of one ton per acre, or nitrate of soda at the ratio of one half ton per acre. Wherever possible, crop rotation should be practiced. This is by far the most effective means of control. Flat-headed Borer (Chrysobothris femorata). This insect is particularly harmful to apple trees but also does great damage to cherries and prunes and even raspberries. Trees that are subject to its attack when planted where it is prevalent should be always protected against the direct rays of the sun, as the eggs are laid on the south and west side of the trees and are only laid on those either sun- burned or subjected to the direct heat of the sun rays. There are some pp—— a — I _——_——, 14 DESTRUCTIVE INSECTS AND THEIR CQNTROL. very good tree protectors on the market made from palm fiber. Two shakes, or even shingles, placed four inches from the tree on the south and west side will effectively prevent injury to young trees from this insect. They will also attack old trees that have become sunburned. Such trees should have the dead bark removed and treated with graft- ing wax. A whitewash with soap and sulphur added also prevents the laying of eggs. The remedy in case raspberries are affected is clean cultivation. Cut down and burn the canes as soon as the injury is noticed. Cut out below the surface of the ground and burn all the old canes in the fall. Leaf-eating Beetle (Diabrotica soror). A green beetle with black spots, so often mistaken for a ladybug, and particularly confused with the Hippodamia convergens (red with black spots), is one of the commonest and most destructive of leaf-eating insects. It attacks a wide range of plants from orange trees to hop vines, dahlias, roses, chrysanthemums, and many other ornamental and garden plants. Many ways of combatting it prove helpful. Of the mechanical, jarring is the best. Early in the morning, while the beetles are cold, place a large umbrella or sheet three feet square nailed to a frame under the plants. A sharp sudden jar will cause the beetles to fall into the umbrella or sheet where they should be quickly transferred to a can containing water with a coating of coal oil on the surface. Mix thoroughly 1 part of Paris green with 10 parts of wheat or rye flour. Dust the plants thoroughly with this, using a coarse cloth bag. Spray the plants with 1 pound of arsenate of lead to 25 gallons of water. These two mixtures are poisonous and must be used with care. A thorough dusting of the plants with powdered tobacco dust will tend to keep these pests away. Strawberry Crown-borer (Tyloderma fragarie). This is a destructive and disagreeable pest to handle. About the only method giving a great degree of success is to watch your vines carefully and when the pest is present, remove any vines showing the wilt result- ing from the attack and burn at once. A careful adherence to this will keep the pest well in check. Inspect your plants very carefully before planting and burn all infested ones. Bean and Pea Weevils (Bruchus sp.). While these insects are very common and destructive they are undoubtedly among the easiest to be controlled. The adult weevil comes from the seed bean or pea we plant, so by treating the seed or planting clean seed we need never be bothered. The treatment of weevil DESTRUCTIVE INSECTS AND THEIR CONTROL. infested seed consists of placing it in an air tight receptacle, barrel or box, with a tight lid. On top of the seed place a shallow vessel contain- ing carbon bisulphide and close the top tightly and allow the gas formed by the evaporating liquid to remain undisturbed for at least six hours. Be careful not to bring any fire near the receptacle, as both gas and liquid are very inflammable. Use 1 pound or more of carbon bisul- phide to 1,000 cubic feet of space. You can not use enough to hurt the seed. Do not allow any of the " liquid to come in contact with the seed. If you are planting on land that has had infested crops the year Fie. 11.—Bean-weevil previous and the ground is apt to contain seed with iia weevils in it, plant a few rows of very early peas to act as a trap crop. When these are nearly mature pull up and feed to the stock. Late planting is also advisable in this case. : Pear and Cherry Slug (Eriocampa cerast). This is the larval form of a small, four-winged saw-fly. It is a voracious feeder and will soon skeletonize the leaves of a tree if not checked in time. It is very com- pletely controlled To by a dust spray GAS of hydrated or air-slaked lime, or even common road dust. The trees should be thickly dusted. It may also be success- fully destroyed by a spray of arsenate of lead, 4 pounds to the 100 gallons of water. Fi1G. 12.—Pear and Cherry-slug (FE. cerasi). a,larva: b, adult. Codling-moth (Carpocapsa pomonella). The control of this insect is the greatest problem of the apple grower. He should, therefore, put forward every effort that will tend to lessen its numbers and with this end in view, it is important to first take into consideration the life of this insect. Perhaps every one knows that the worm of the apple is the young or larval stage of a tiny brown moth with bronze tipped wing, which lays its eggs in the early spring on the leaves. This egg hatches into a minute worm which enters the blossom end of the small apple and works its way into the core. After reaching maturity, it bores out and crawls down the tree, spinning a small cocoon under the loose bark or in any bit of sacking or other material left in the erotches or about the tree, where it changes into an adult moth. This moth lays its eggs on the fruit or foliage and the young on hatching eats off a small patch of the skin and bores into the apple, continuing the 16 DESTRUCTIVE INSECTS AND THEIR CONTROL. work of destruction, and increasing as it does hundreds for every one of the first brood, it is plainly seen that each of the moths of the hold over winter brood destroyed in the spring means the destruction of many thousand worms, as there are three broods in many of our sections, and they lay upwards of 100 eggs apiece. The moth that comes out in the spring, has hibernated during the winter in the larval form, securely inclosed in its small brown cocoon, which is as securely provided for and protected by us in our packing houses, neglected picking boxes, old sacks and bands left in an isolated place, the crotches of trees, etc. One large packer has demonstrated that the moths decreased in geometrical ratio from his packing house to the farther edge of his orchard, and while the apples on the trees close to the house contained no apple free from worms, those one half a mile away had only a small percentage of worms. The first and most essential step of all in the control of this pest is the prevention of this hibernating brood from entering our orchards. Our packing houses should be tight with screened doors and windows. The houses should, if possible, be so constructed that the portions in which the moths hibernate may be fumigated. It is also possible by means of tight floors with gutters around the FiG. 13.—Codling-moth larva (C. pomonella). walls containing water and kerosene to prevent the worms entering the walls or crawling underneath the floors. The removal of old loose bark, dead limbs, the closing of cracks or holes with cement is also an aid in this work. While it is true of most insects that a campaign of sanitary measures will go a long way towards its better control, in no case is it so evident as with this moth, but in order to fully benefit by these means, all the orchardists in the district must adopt the same system. We have found that the best spray material for the control of this pest is arsenate of lead, and this can be used 4 pounds to 100 gallons of water without fear of injury to the foliage. It also adheres to the leaves and resists the weather conditions better than Paris green. The first spraying should be just after the bloom falls and the calyx is still open, to be followed tt weeks later by another. For the time of the third spraying, watch carefully a few banded trees, and when the worms have reached the pupa state, spray so you will catch the second brood. This should be about eight weeks after the first spraying. On fall and winter apples use another spray the middle of August. prunes, and DESTRUCTIVE INSECTS AND THEIR CONTROL. There are several natural enemies of the codling-moth in California which tend to reduce its numbers. We also have, at the State Insectary, an imported enemy in the form of a hymenopterous parasite, Callie- phialtes messor, which preys on the moth in its larval stage, just after it has spun its cocoon. Since it has been under observation in confinement its work has been very satisfactory, and now an effort is being made to acclimate it to our California orchard conditions. Colonies can be pro- cured by addressing the State Insectary, Sacramento. Pear and Orange Thrips (Euthrips pyri and E. citri). The pear thrips is one of the worst insect pests commanding our attention just at present in the deciduous orchards, especially of pears, cherries. This insect is neither a biting nor sucking insect, |: ~ but is in a class by itself. It extracts its food from the interior por - tion of the host plant in such a manner as to m a k e poison- ing an impos- sibility. Its favorite point of attack is the interior por - tion of the bud or bloom, de- stroying the stamen and pistil and in- juring the pet- als. It even attacks and de- stroys the em- bryo fruit and seriously in- jures the young, tender leaves. The damage to the blossom and embryo fruit is the work of the adult entirely, while the young devotes its atten- F1G. 14.—Thrips injury to Bartlett pear leaves iCourtesy U. 8. Dept. Agr. 18 DESTRUCTIVE INSECTS AND THEIR CONTROL. tion to the tender leaves and fruit. The blossoms turn brown and drop, the leaves curl, and the fruit scabs. In the case of the orange thrips, while the fruit is not destroyed, it is scarred in such a manner as to greatly reduce its value. This attack on the orange can not be confused with any other injury as it always takes a very regular form in the shape of a brown ring around the navel end, and often also the stem end, with a EE. times connecting the two. The pear thrips spends nearly eleven months of its life in the ground. The adult lays its eggs in the tender portions of leaf or fruit stem. The young, hatech- io ing, passes rapidly through its a different larval stages, then drops to-the ground, where 1t F1c. 15. Thrips injury to Jtse) Butiett pear. works its way down a few inches, hE and making a small cell, passes the winter in its pupa state. The most efficient remedy yet found for its control is a spray of black-leaf tobacco extract, when the insect is on Fi1G.16.-—Thrips (E. pyri). a, adult; b, larva, greatly enlarged. the tree early in March. Also fall plowing. The following formula is taken from U. S. Department of Agriculture Bulletin No. 80 by Dudley radiating streaks of injury some-- ESR ——————— ES tad DESTRUCTIVE INSECTS AND THEIR CONTROL. 19 Moulton. Use black-leaf 1 part to 60 of water in combination with a 2 per cent solution of distillate emulsion. ‘The black-leaf tobacco extract may be purchased from local agents. The distillate oil emulsion ean also be purchased from local dealers in plies, but is prepared after the following formula: 12 gallons. 30 pounds. 20 gallons. spraying sup Hot water Whale-oil or fish-oil soap Distillate oil (28° Baumé) The soap is first dissolved in a kettle of boiling water and then removed to the spray tank, where the oil is added. This should be agitated violently and sprayed out under pressure of from 125 to 150 pounds into other parrels. This stock solution contains about 59 FiG. 17.—Thrips injury to oranges. Courtesy U. S. Dept. Agr. per cent of oil, and should be diluted at the rate of about 2 gallons of the emulsion to 48 gallons of water for a 2 per cent solution. The secret of making @ thoroughly good stock emulsion lies in having the soap and water boiling hot, in adding the oil to this solution, and under mo circumstances in adding the soap and water to the oil, thorough and violent agitation, and, finally, in passing it through the spray nozzles under high pressure. It has been found by repeated experiments that high pressure 18 the most important factor, and an d once through the pumps and nozzles under pressure emulsion passe | oved by repeating this of from 156 to 160 pounds can not be impr operation. Fish-oil soap may be made as follows: gallons. pounds. Fish oil Place the water in a cauldron, boil slowly for about two hours. or about a 5-gallon mixture.”’ add the lye, and then the fish oil, and This will make about 40 pounds of soap vol ~~ A 20 DESTRUCTIVE INSECTS AND THEIR CONTROL. Bean Thrips (Euthrips fasciatus). These insects are often taken for aphids. They are much longer than the aphids but not so large, move more quickly, and are of a yellow color, with orange spots. They work on the under side of the leaves and the pods of peas and beans. The only remedies giving any satisfaction are an undershot spray of tobacco extract, 1 part to 50 gallons of water, and sulphate of nicotine, which used at the ratio of 1 ounce to 5 gallons of water has given perfect success against this pest. The past year we have found the thrips prevalent on alfalfa, peach and pear trees. Care should be taken to spray these cases carefully, to stop this new pest before it has gained the prevalence of the pear thrips. Plant Lice, Aphis. These insects, while of small size, do an immense amount of damage to every variety of vegetation. They are provided each with a sucking tube, with which they draw out the sap of the plant. As to habits and MAGNIFIED NATURALSIZE MAGNIFIED NATURAL SIZE c Fie. 18.—Syrphus Fly. a, larva; b, pupa; adult. Parasitic on Aphis. propagation, they differ widely as separate species. Some have winter forms feeding on the roots and summer forms on the leaves and stems, others remain always above ground. They are protected and utilized by ants, as the ant is particularly fond of the excreted honeydew of the aphis. It is, therefore, essential to fight the ants at the same time in many cases in order to successfully combat the lice. This is accom- plished by jarring and then placing a barrier to prevent the ants reclimbing the tree. A good barrier is made by binding strips of tanglefoot fly paper 4 inches wide around the trunk, with the sticky side out, applying in such a manner that the ants ean not erawl under- neath. "SPRAYS: Black-leaf extract 1 part to 50 of water. Sulphate of nicotine 1 part to 750 of water. Kerosene emulsion : Coal oil (150° test) Dissolve the soap by boiling in the water, and when dissolved and while boiling pour with a dash into the kerosene. Churn the mixture for ten or fifteen minutes, either by pouring back and forth from one DESTRUCTIVE INSECTS AND THEIR CONTROL. vessel to another, or by the use of the pump by pumping the liquid back upon itself. The emulsion should have the consistency of cream. No. 1: For a winter wash when trees are dormant, use 1 gallon of emulsion to 6 gallons of hot water. . No. 2: For a summer wash use 1 callon of emulsion to 10 gallons of hot water. The natural means of control, such as ladybugs, internal parasites and syrphus flies give the best success in most cases. For colonies of these apply to the State Insectary, Sacramento. : The Woolly Aphis (Schizoneura lamgera). Black Peach Aphis (Aphis persice-niger). These two species of plant lice spend the winter on the roots of the host plant and the summer on the portions above ground. The woolly aphis attacks apples trees, forming the characteristic root deformations, and the new growth above ground forming the white woolly masses of insects sO conspicuous on the new bark growing over scars OT cuts and the axils of the leaves or on new growth. This aphis passes the winter in the ground on the apple roots ee : . Fig. 19.—Woolly: Aphis (S. lanigera). a, root injury and crawls up 1m the spring by subterranean form: b, wingless, andc, winged s aerial forms. — to the new growth. This summer form produces winged individuals that spread the pest from tree to tree. The first essential in fighting this pest is to be sure when you plant a new orchard to "accept only absolutely clean trees from the furseryman. Reject any and all that show the least sign of infestation. It is also a very goo ‘plan to always immerse young apple trees in a solution of whale-0iL soap and water, 1 pound to 5 gallons (have the water warm to 90 degrees) before planting. If an orchard is already infested, the grower will have to fight both winter and summer forms. For the winter form, dig a shallow trench around the tree in the fall of the year, and place in this about two or three shovelfuls of wood ashes, or better, if it can be procured, 2 to 3 pounds of tobacco dust. The lye or nicotine leaching out, is taken downward and destroys this root form. The use of tree tanglefoot in the form of bands very early in the spring will prevent them ascending the tree. For the summer form, apply kerosene emulsion, Or tobacco extract. These aphids are attacked by many of our ladybugs and care should be taken not to destroy these friends. RRR DESTRUCTIVE INSECTS AND THEIR CONTROL. The black-peach aphis is a shiny black plant louse which clusters in great numbers around the young leaf stems and buds. It has the same habits of life as t his, but is more destructive and harder to ™ combat. The same remedies, while good, will not altogether control it. The ground form can best be destroyed by the application of carbon bisulphide to the soil. Make the holes around the tree from 6 inches to 6 feet away from the trunk and about 2 feet apart. These are easily made by means of a large crowbar. Put in about a tablespoonful in each hole and close tightly. If the soil is well soaked with water on top immediately afterwards it lessens the ye escape of gas. Be careful in applying Fic. 20.—Cluster of Black-peach not to have the carbon bisulphide come aphis (4. persicae-niger). : . s ‘ into direct contact with the roots, as 1t will surely kill them. Wherever available a fumigation with hydro- cyanic-acid gas is the surest remedy for the form on the twigs. Orange Aphis (Aphis gossipt). Is peculiar in that it attacks oranges and melons. On the orange trees it very seldom requires any treatment whatever as a minute internal parasite keeps it completely in control. In the case of the melon, it is a difficult pest to handle. The parasites do not seem to appear of them- selves, but have to be introduced as soon as the lice make their appear- ance. We find that the best natural enemy of these lice, however, is the black spotted, red ladybug (Hippodamia convergens) which we gather in quantities while they are hibernating during the winter and liberate in the spring on the first appearance of the aphis. The young vines should be watched very carefully and application made to the State Insectary, Sacramento, as soon as any lice are noticed. Rose Aphis. One of the most destructive and common of the garden pests is the rose aphis. This insect can easily be controlled by a spray of tobacco extract, 1 to 60 of water, or the kerosene emulsion No. 2, or whale-o1l soap or fish-oil soap, 1 pound to 6 gallons of water. For formulas for soaps, see Pear Thrips. DESTRUCTIVE INSECTS AND THEIR CONTROL. Green Apple Aphis (Aphis pomi). Prune Aphis (Aphis prunifolin). These aphids pass the winter in the egg state above the surface of the ground. The essential step in their control is clean trees. Spray in the fall with either lime, sulphur and salt, or concentrated lye F16. 21.—Green Apple Aphis (4. pomi). Courtesy U.S. Dept. Agr. (1 pound to 7 gallons of water). This will remove the moss as well as destroy many of the eggs which are protected by the moss. The summer treatment consists of kerosene emulsion or tobacco extract, both applied warm. Our common California ladybugs (Hippodamia convergens and ambigua) as well as the Syrphus flies, are voracious 24 DESTRUCTIVE INSECTS AND THEIR CONTROL. feeders on these lice. We should use every means to introduce these friends into our orchards. ; The green apple aphis is readily told by its peculiar effect on leaves and fruit. The leaves curl very badly and the fruit is deformed, having a shriveled appearance, and when cut open the interior looks as if small portions of the skin were distributed all through it. | Hop Louse (Phorodon humulr). This is a very common and sometimes destructive enemy of the hop. It should always be carefully watched and if found prevalent, spraying should be resorted to. A knapsack pump, or a barrel pump with two nozzles, drawn on a sled, are both satisfactory. Our common red and black spotted ladybug (H. convergens) will keep it in check if intro- duced into the yard early enough. The State Insectary has them for distribution. For sprays, use sulphate of nicotine, 1 to 750, or, QUATEIT CHIPS. «cs vvrnny iv drnansasmmpnsasrensspnsrtany 8 pounds. Whale-o0il soap or fish oil........ccvervenrennererenenn 12 pounds. A RADE EERE PR EEE Foie dame a 100 gallons. Soak the chips eight to nine hours in hot water. Dissolve the soap by boiling. Add hot water to make 100 gallons. Use a fine spray nozzle. See Pear Thrips for a formula for whale-oil soap. Cabbage Aphis (Aphis brassice ), This aphis is one of the worst pests of the cabbage. It can be easily controlled by a spray of tobacco extract (1 to 50) before the cabbage begins to head. Also apply to State Insectary, Sacramento, for a colony of parasites. San Jose Scale (Aspidiotus perniciosus). Greedy Scale (Aspidiotus rapa 2, Italian Pear Scale (Epidiaspis pyricola J). These insects succumb readily to. the lime-sulphur wash. ETE rs ahs ssn rvs faving adv ess Fema un sve inlanis £2 200s 33 pounds. SOIREE. tresses iad ire dais nen sn a Keats ot 66 pounds. AVRIL ic eensvsssnssnbosssrntssunsstsioansassasnns 200 gallons. In every case where the trees infested are covered with moss, it is always advisable to spray with a fungicide. Lye is the best, 1 pound to 7 gallons of water, applied the first of December. Allow the moss to be washed off by the rain, and then apply the lime-sulphur, while the trees are still dormant. TY 1 i) lyx end of the DESTRUCTIVE INSECTS AND THEIR CONTROL. 25 Greedy scale (Aspidiotus rapax). More attention must be paid to this scale on apples, as much fruit is rejected on account of this insect. It generally col- lects in the ca- fruit, where it escapes the eye of all, excepting the expert in- spector. It 1s about the size of an ordinary pinhead and of a dirty gray color. Is almost round and not nearly so flat as the San Jose scale and has a conspicuous raised portion just a little to side of center. Use two spray- ings of lime-sulphur, allowing two weeks interval at any time during the dormant period of the trees. Fic. 22.—Greedy Scale (4. rapax) in calyx end of apple. The San Jose scale (Aspidiotus perniciosus) is well kept in check by its numerous parasites in this State, there being no less than five, an internal, Aphelinus fuscipennis, and ladybugs Chilocorus bwulnerus, C. similis, C. cacti, and Rhizobius lophante. Of these bivulnerus and lophante are very active. The San Jose scale is readily distinguished from any other attacking apples, as when it attacks the fruit (and it always does) it causes a small, round, scarlet spot. White rose scale (Aulacaspis rose) infesting rose, blackberries and raspberries, ete. Use a whale-oil soap spray, 1 pound to 5 gallons of water. “Apply warm, about the first of June, and if possible dig away the earth exposing the crown before applying spray. The old canes, badly infested, should be removed carefully in the winter and burned. Always cut them below the surface. Brown apricot scale (Eulecanium armeniacum) and frosted prune scale (Eulecanium pruniosum) on prune and apricot trees. Address an application to the State Insectary, Sacramento, on or before the first DESTRUCTIVE INSECTS AND THEIR CONTROL. a DESTRUCTIVE INSECTS AND THEIR CONTROL. 27 of May for Comys fusca, the wonderful parasite that keeps it in check a It is never advisable to apply any remedy for the cottony-cushion so well. Black scale on apricots. Send to State Insectary for colony of 1. scale, but send to the State Insectary for a colony of Vedalia cardinals, parasites, Scutellista cyanea and Aficus lounsburii. i i its parasite. This scale attacks all / i kinds of citrus, acacia, pittisporum, Purple Scale (Lepidosaphes beck). eb rose, and broom. It should not be con- | Red Scale (Chrysomphalus auranti). § fused with the mealy-bug, which is also | Black Scale (Saissetia ole). “1 white, but moves freely throughout its | Yellow Scale (Chrysomphalus aurantii var. citrinus). . life while the scale does not. Always Soft Brown Scale (Coccus hesperidum). in give the parasites a trial when you have | Cottony-cushion Scale (Icerya purchasi). | ' black scale on citrus or olive. But where you have red, yellow and purple scale, use hydrocyanic-acid gas fumiga- tion. (See page 29.) Phylloxera of the Vine. (Phyiloxera vastatriz.) The mere mention of this insect causes alarm among grape growers in every locality as yet unvisited by its ravages. It would be a hard matter to compute the immense damage in dollars and cents in California alone, to say nothing of European countries, accom- plished by this microscopic insect pest of the grapevine, and although immense sums have been offered for a cure, no satisfactory method has ever been de- vised to control or limit its destructive- ness, with the one exception of the | : removal of all European varieties of | ‘vines on their own roots, and the plant- ing of all varieties on the stock of the native wvitis vinifera of America. While these vines are not entirely im- mune in all cases, there are some which are absolutely so, and as space will not permit of a detailed account of them here, we will refer you to any reliable nurseryman who can supply this in- RE REN FiG. 24.—Red Scale (C. aurantii). a, natural size on leaf; 06, female scale greatly formation. enlarged; c, male scale enlarged. Phylloxera attacks the roots, causing Fie. 25.—¢ ations cushion Scale . ) i } . purchasi). : We have at present parasites that completely keep in check the soft small swellings which decay, resulting | brown scale, the cottony-cushion scale and the black scale in almost ] in the death of these roots. The death of the vine is accomplished in every district, and the yellow scale in certain places. from one to many years, according to the general vitality and resistancy of the vine. 28 DESTRUCTIVE INSECTS AND THEIR CONTROL. It is transmitted to new localities on the roots of young vines and on grape boxes during the picking season. In some sections of California winged forms occur which also help its more rapid spread. In a vine- yard it travels from vine to vine on the roots and by careless cultivation through infested spots. The presence of the insect is first manifested by a decreased growth of canes, small bunches of grapes very deficient in sugar, and a premature yellow coloring and dropping of the leaves. The rapid spread may be in a measure checked by the removal of all infested and surrounding vines for at least two rows and the burning of these in the center of portion removed. Plant this portion to grain for one or two years, then replant with resistant stock. Careful inspec- tion of incoming nursery stock and the absolute refusal of all such from known and infested regions is the only preventive. ¢ DESTRUCTIVE INSECTS AND THEIR CONTROL. FUMIGATION PRACTICE. The process commonly spoken of as fumigation, in California, con- sists of the chemical combination of water, sulphuric acid, and cyanide of potassium in such quantities as to produce the greatest amount of hydrocyanic-acid gas possible for the least cost. ® The most economical ratio and basis of dosage is 1 ounce of cyanide, 1 ounce sulphuric acid and 8 ounces water. For field work a tent is used, made preferably of 8-ounce duck, octagonal in shape, and numbered as in figure. In the case of the largest sized tents, 6-ounce duck may be substituted for the sides or flaps to reduce weight. It is- customary to use a filler to pre- vent the rapid leakage of gas, the best so far being the oak ooze, such as used in tanning. The tents should be dipped, then when partly dry redipped and spread out and dried. The trees should be trimmed so that no limbs are less than 114 feet from the ground. The tent is placed over the tree and the bottom made as tight as possible, and an earthen crock is then placed under the tented tree containing the proper amount of water to which is added the acid and then the cyanide. To compute the correct dosage take the sum of the two numbers on the tent where the sides touch the ground, then find the distance around at the bottom by either pacing or measuring with a tape line. Now apply these two figures to the dosage schedule as given in Figure 27. As to the proper dosage to use, I submit the following statement by Frederick Maskew : In considering the following statements it should be borne in mind that the writer is dealing with this phase—the dosage—of fumigation from the standpoint of commercial work. This is the class of work that the great majority of citrus growers pay for, and which produces the good, bad or indifferent results in their orchards each year. Any attempt to set an arbitrary fixed dosage to be used against any or all insect pests of citrus trees in all parts of California is fareieal and misleading for the following reasons. The difference in degree of resistance to damage on the part of the fruit of various varieties as also the same varieties at different periods during the fumigating season, the difference in the texture of the material from which the fumigating tents composing the various outfits now in use throughout the citrus region are made, also as to whether they are treated with a filler or not, and the difference in the locality where the operation is performed. SENT ANP R e 30 DESTRUCTIVE INSECTS AND THEIR CONTROL. A well trained crew of fumigators supplied with a full set of 32 tents, averaging eight sets a night every night, Sundays included, would require from the 15th of July until the 22d of December to cover 400 acres. No such continuous record ever was or ever will be made. Hence the period will be longer. Stop for a moment and think of the change that takes place in the size and resisting power of the fruit during that period, and the fallacy of attempting to set a fixed Fi1G. 26.—Method of Marking Tent. dosage will soon be apparent. No fruit grower will continue to permit his erop of oranges to be burnt up for the sake of destroying the annual crop of bugs in his orchard. With the amalgamation of the different ideas of the various agents of the Bureau of Entomology, U. S. Department of Agriculture, as exemplified in the system of fumigation introduced in southern Cali- fornia, the question of a safe and efficient dosage has been simplified and placed” within the comprehension and power of any one with ordinary intelligence. wy Blur id RRR “~< DESTRUCTIVE INSECTS AND THEIR CONTROL. Any fumigator, professional or otherwise, can settle the question of a safe dosage adapted to the quality of his own tents, in any orchard, at any time, or in any locality, by a very simple procedure. For example: Take a set of marked tents and cover ten or twelve trees. “With a No. 1 schedule obtain the amount of cyanide called for by the dimensions of the tented tree. Deduct one fourth of this amount, for each of two trees; deduct one eighth for each of two trees; use the Distance around tree, S 2 et Q >» =] [= © 2 > a Fic. 27.—Dosage Schedule No. 1. full amount for each of two trees, add one eighth for two trees and add one fourth for two trees. be plainly in evidence the next day, be found within the range given above. The value of Schedule No. 1 to the fruit growers of California will hich to compute a uniform be found in its service as a base from w dosage for any and all purposes of orchard fumigation. Having found the limit of resistance on evidence of burning, it will be w a The burning effect, if any, on the fruit will and it is fair to assume that it will the part of the fruit by the ise to use the maximum amount below 32 DESTRUCTIVE INSECTS AND THEIR CONTROL. that point as the dosage at that time. With the possible exception of red and yellow scale, it invariably happens that almost every tree in the orchard has some scale upon it, so much more advanced in develop- ment and consequently harder to kill than other of the same species - that it requires the strongest dose the fruit will safely stand to accom- plish a clean up, and in many instances even this fails to do complete work. It is, however, an easy matter as the season advances for the fumigator to keep in touch with the danger line, by increasing the dose one eighth or a quarter on a few trees during the night’s work and observing the effect on the fruit the next morning. Mealy-bug (Pseudococcus citri, P. longispinus). This is one of the most serious pests on citrus trees at present and we are sorry to say seems to be on the increase in spite of all measures of control. These insects are often confused with the cottony-cushion scale, but is similar in no respect excepting the color, white. P. longis- pinus differs from P. citri in that it has con- Mm spicuous white filaments about the length of the body protruding from the posterior portion of the body. Longispinus is most commonly found in hot- houses while both occur on outside trees. They move Ld 4 freely about the plant Fic. 28.—Mealy-bug; a, P. longispinus; b, P citri. throughout their life. The scale lays eggs in the white cottony mass. The mealy-bugs are wont, when very thick, to collect in large clusters. They attack all varieties of citrus, oleander, rose, palm, and almost all varieties of hothouse plants; in fact, they are probably the worst of all hothouse pests. We have a very efficient ladybug parasite (Cryptolacmus montrouzieri) and also a new internal prasitic fly from Japan. Just now in the northern portion of California, another of the ladybug family (Scymnus guttu- latus), is doing excellent work in destroying the mealy-bug. These, however, only do well on vegetation outside and not in greenhouses, where fumigation must be resorted to. One of the best methods in use now is a nicotine saturated paper, which is burned in the houses. This does not injure the tender foliage and will kill lice and the mealy-bug. For outside work on hardy trees and plants, hydrocyanic-acid gas is preferable. This insect is becoming one of the most dangerous of our orchard pests, and its presence upon nursery stock should demand rejection. DESTRUCTIVE INSECTS AND THEIR CONTROL. 33 Nematodes or Eel Worms. While these small worms are not in any way related to insects, we will treat of them, as their damage to plant life is somewhat similar to insect attacks. These worms belong to the family of true worms (Vermes) and there are many species, very few of which are really detrimental. Most are scavengers, living on decaying vegetable matter. Those destructive in this State so far confine their attacks to roots of grapes, peaches, and figs. They seem to be worse in certain ‘soils and conditions, their preference being for rich, heavy loam. The injury takes on the form of small, bead-like knots on the roots, inside of which the tiny worm is coiled. They are microscopic in size and can not be seen with a less magnification than 20 diameters. No successful method of combatting them has been found, so it is very essential that nursery stock should be thoroughly inspected and destroyed when found to contain them. Tobacco dust as a fertilizer would help greatly to remove them from the land after once established. Slugs and Snails. These are troublesome pests that are very general feeders and very destructive. There has never been a method more successful than hand- picking and traps. When you wet down your garden at night, place pieces of boards or cabbage leaves near where the vegetation is dense, such as violet beds, ete. The slugs will congregate under these traps and can easily be killed by dropping into hot water or simply snipping them in two with a knife or small shears. They can be poisoned to quite an extent by the use of 1 part of Paris green to 10 parts of flour, placed in small mounds. This should not be used if any fowls or animals are in the yard. Bantam chickens are of great help in cleaning up a yard infested with these pests, as these chickens do not scratch and are very fond of the slug. Slugs feed at night, and if you are an early riser you will find them returning to their day covers between five and six in the morning. i ail aianney DESTRUCTIVE INSECTS AND THEIR CONTROL. INSPECTION OF NURSERY STOCK. The rigid inspection and disinfection of nursery stock is the first essential of clean fruit culture. Recognizing this, the horticultural laws of California are so formed that they protect the individual grower against loss from the careless nurseryman and the community from the invasion of destructive fruit pests. Upon the arrival of all trees, plants, bulbs, or seeds at their destination, the County Horticultural Commis- sioner, or in case there is no commissioner in that county, the State Commissioner is notified by the railroad or express agent of the fact. The trees are then held by the agent until inspected by the county or State authorities before receiving the freight charges and releasing to the owner. If, upon inspection, the trees or plants are found to be infested with insect pests or diseases not found in the orchards, vine- yards, gardens, or farms of California, such infested shipments shall be immediately sent out of the State, or destroyed, at the option of the owner, owners, or agent at his or their expense. If, on the other hand, these shipments are found to contain insects or diseases known to exist within the limits of California, then the entire shipment must be disinfected at the expense of the owner or agent, and then held in quarantine until the necessary time has elapsed to determine the result of the disinfection. If it has been performed so as to destroy the insects or disease in a manner satisfactory to the inspector, the shipment is released; if not the treatment is repeated until the desired result is attained. In dealing with intercounty shipments within the State of California, it is the custom of the county commissioners to follow the plan of the State law; that is, all nursery stock found infested with insects not found in that county are strictly prohibited, while shipments contain- ing insects known to exist in the county are disinfected until such infestation is removed. The methods of disinfection vary for different kinds of stock. For all seed, such as cotton, beans, peas, alfalfa, grains, carbon bisulphide is used. Place the seed in an air-tight box or barrel, with at least a four-inch space at the top. Place the carbon bisulphide in a shallow dish on the top of the seed, then close tightly for from six to twelve hours. (Do not allow the liquid to come in contact with the seed or bring a fire close to the ‘barrel, as both fumes and liquid are highly inflammable.) Use one pound or more of carbon bisulphide to each DESTRUCTIVE INSECTS AND THEIR CONTROL. 35 1,000 cubic feet of space. This method is also successfully employed ' on vine cuttings for phytoptus and phylloxera. Rooted vines from a phylloxera infested district should never be admitted into a county or section not infested with this insect. For all forms of plant bugs, scale insects, plant lice, ete., occurring on nursery stock, the best method is the hydrocyanic-acid gas fumiga- tion for adult or larval forms, and whale-oil soap solution for eggs. Use this warm, 110 degrees, and in the proportion of 1 pound of soap to 5 gallons of water. The fumigation process, which may be used three times its ordinary strength on dormant deciduous stock, is as follows: Place three ounces of water in an earthen crock, add to -this.one ounce of commercial sulphuric acid, and when they are thoroughly mixed, add one ounce of eyanide of potassium, this amount being suffi- cient for 100 cubic feet of space. Fumigate in an air-tight room or box, or use an oiled canvass sheet. Always place the crock in the box or under the canvass before placing the cyanide in the solution, as the gas’ escapes rapidly and is deadly to the human as well as the bug. Fumi- gation should continue for one hour or longer. Be careful in opening the fumigating box or sheet to not breathe the fumes, and do not attempt to remove the trees until they have aired for at least thirty minutes. Be sure the trees are dry before fumigating, for if covered with moisture damage is sure to result In the case of citrus nursery stock we advise a complete defoliation after which the fumigation process as given is correct. In case the leaves are not removed, the trees must receive the same treatment as commercial orchards and not as given for dormant deciduous stock. We believe that the defoliation is really a benefit to the tree and cer- tainly insures the more certain destruction of the insect pest. In inspecting for woolly aphis, peach root-borer, and other root infesting insects, thoroughly wash the roots by shaking carefully in a receptacle of water. Do not use a hose as it will dislodge the insect or evidences of its presence. In cases of bacterial diseases such as root knot and olive knot or nematode galls and peach root-borers, no effect- ive treatment is possible, and the stock should always be destroyed. For suspected cases of peach blight or rose rust or other fungus diseases, dip in a strong Bordeaux mixture, composed as follows: Copper sulphate (bluestone) 8 pounds. QUICKIE + oovvvrere ee 10 pounds. — Water 50 pounds. Dissolve the copper sulphate (bluestone) in a barrel containing 10 or 12 gallons of water. Slake the quicklime and thin it to a ereamy whitewash. Pour the whitewash very slowly through a wire screen 36 DESTRUCTIVE INSECTS AND THEIR CONTROL. into the copper solution. Stir the mixture thoroughly and add enough water to make 50 gallons in all. Stir occasionally while applying as a spray to the trees. In the preparation of the Bordeaux mixture it is necessary that the ingredients should be mixed in a wooden vessel. If an iron one is used the copper will go to the iron and the effect of the spray is largely neutralized. Apply the wash cold and as soon after it is prepared as possible. Never allow it stand over night. Solutions for insects on nursery stock: Black-leaf tobacco extract 1 gallon. Distillate oil emulsion 2 gallons. 50 gallons. A good distillate emulsion is prepared as follows: Hot water 12 gallons. Whale or fish-oil soap 30 pounds. Distillate oil (28° Baumé) ........ccoveevnrinnrianrennnes 20 gallons. Dissolve soap in the boiling water and place in spray tank and then add the oil. Agitate violently and spray into barrels. This stock solution contains 55 per cent oil. Place 2 gallons of this in 48 gallons of water for a 2 per cent solution. To be used warm on thrips and aphis and other soft bodies insects, as plant bugs and young scale. Kerosene emulsion: Coal oil (150° test) Laundry soap Water Dissolve the soap by boiling in the water and when dissolved and while boiling pour with a dash into the kerosene. Churn the mixture for ten or fifteen minutes, either by pouring back and forth from one vessel to another, or by the use of the pump by pumping the liquid back upon itself. The emulsion should have the. consistency of eream. To be used for aphis and young scale. Lime-sulphur wash (used warm, 100°) for all scale insects similar to San Jose scale, greedy scale, rose scale, ete.: 33 pounds. Sulphur 66 pounds. Water 200 gallons. To prepare, slake the lime with warm water enough to do it “thoroughly, and during the process add the sulphur. Boil for one hour with just water enough to prevent burning, and, if it then forms a deep, amber-colored liquid, it is done, and warm water may be added to reduce to spraying strength. In the case of hardy hothouse plants, such as aspidistra, laurels, ever- DESTRUCTIVE INSECTS AND THEIR CONTROL. 37 green trees, bulbs, roots, deciduous vines and trees, a fumigation of forty minutes of the same strength and under the same conditions as given for dormant deciduous stock can be given, providing the plants are perfectly dry. They should be placed in the fumigating house and the air thoroughly dried by means of oil heater, and then, after fumi- gation, left in the house for twenty-four hours, or removed to some place where they will not become moist for at least that length of time and preferably longer. In the case of palms, ferns, orchids, begonias, ete., hydrocyanic-acid gas must not be used. These can be sprayed with a nicotine solution. (We recommend black-leaf 1 to 60 or mico- tine sulphate 1 to 750, or use some form of nicotine fumes such as the saturated nicotine paper manufactured by the people supplying black- leaf.) pn mT TE i ti 3 fh § ¥ 4 AACS JoUDSDUTIY o.oo. a 26 Aphelinus-fuseipenpis .........:._ cocoon 0 go cp ee DEE 25 APHIS CT ae ee See 20 ADDIE oo... NE a a 23 Black. Peach ............. . . oo coo son Nae 21 Cabbage .............. 0 Ll oe ee a 24 BOD S.-i URAL 24 Pangea OR Re ie 22 Prime... oo... al ULES ae ae eT RE 23 Bose ...........c..o oi aig mas 22 Woolly... ...... pte ns mr eR 21 ANS eens aE Ee TS eT 20 Brown Day moth... ...... 00... coo hoses en nen 8 Calbaoe-worm ......... 0.0.0. [2 lone ene te RT 9 CankerWorm _.............. co loli os suid nn tl LE eR 8 Ohilecorus bivalnerus ........ 0.0... oon ond ie GUE 25 CROCE eile Rp ee Ne 25 Simills lo... oan cd a dl 25 Codlingemoth ............... 0... Cgpiowe boa Een 15 Codling.moth parasite ......... ..0i. o.oo 0 oan ing ee 17 Qomysfuses _.. __.... ...... [0 cloooando ooo cin suing 26 Corn Worm... i. lhl hoe ns pe Ee ee 7 Oryptolemusmontrouzier ...... i... ._ >... ooo nan BE ee 32 Cut Worm ......... ia ne 11 DIabLOtONEOTONr oo... ee isan fi RT eB 14 Halse Chinchobus o.oo pein Da nh ene 12 Flatheaded Apple-borer -......oo..o..oi i fo in a Pas 13 Fumigation Practice ........ o.oo i ron uae ne an vk de ne 29 Grasshoppers... ..... ..... oli ll Loto oe a 11 Harlequin Cabbage-bug -....c coo... oilc Lo Co An ee a 12 Rippodaminambigun ............._ ....... fei os co red Bl 23 COYLE ORS oC ..umsnren dscns vd nds sam ni br chm enh mend ada pi 14, 22, 23, 24 Inspection of nursery stock... iol noo ii REL 34 Moly oon eae Ls ei Eh 32 Bes cc... enone seid i a a D5 DL RR RIERA HM Loa ee 33 Peach IROOLDOPEr - «vo nso ch mm nna amis ben Se bmn mab da iret) RE 7 Beach WISER. oc ovo ani ernst ch mk Ss mwas ome ao oR SE 6 Pear and Cherry Blue... i rm ee 15 Pearaeal Blister Mite. ........cc cocoa idian ie pT Re Te 6 PHYHOXEPR VASIOEPIR .. eco nin abit sens meh Ca Tei im pir A I Si 27 NOBLE irene ccnsc nnn imme Sma ae Mars esas san en ae 5 Pteremalug PUDSRIID coo. i iii pha Ta a 9 Bed-Hump ‘Caterpillar ......... ou. cvrecseraesiosoin cL TR 11 RUIZ0bIUS JOPBAIITE coco ai hiiema duno sm os ome to hme LET 25 BORIS, BIACK iain emai narnia a Samah be da CS 26 BYOWR Apricot... aa a Er 25 CotioRFReusion coi. Xan Ty A Se 27 Greedy INP... -— — Scymnus guttulatus StUtelligid CYMER av... veeasrrrsnmennanmsananmnnese nnn TIRE 33 Slugs and Bho... een armen mem as 4 OLS GF thu=rs vem aan anes nna Ry mean 12 BOHARH PRE rex enn omen mmr rn meen mmm rai 14 RIAWIRITY SCPOWHIOIOL Lusennaseemmomemnnemmmmmnns rr Ton oT ot sina 20 Syrphus fly SFr sunsrmsensmntdesann enn nn gi ee 9 IDACHINAEHY. oro ocomemmma mesa m mmm me 9 ERE COLOIIIIIER oc... anatime mmmm mmm al, 20 PREIS AEH ©» conv oro meme nr mmm E useiia emma 17 BEANZE occ nomsmr mma smme mem me ae 17 PORE fos unarmed ms mmm LL Ln 10 PUSEOCKSINONN ooo on -= enw etras=sman mma mm mn nn 27 Kefalin CATGIBANS ooovameermeammmeamr mmm eeu pean 14 Woevilz Dean dati DOR... co ~pesar-cememn mmm TT eam 13 AVIre-WOTIS -.o.~-- === 7 ==em=sresmu=mssennzn mmm nrmmee INDEX OF REMEDIES. ia )8 Arsenate Of 108d... ooo - = ~sovnmr senna iis tesniinat 19, 20 BRCE-IGAEISEIA0E o. on nx nr mm iunmremrmammmpmmm mmm nam mE Er ITT en 19 Black-leaf extract and distillate da on el 35 BordefilE MISTI... --vuum=emnseamssmem mm mmmnna monn nT IRI TIT eeeeennnn 34 Carbon BiSuIphige. .. ... ---coummmmemmmmmmmmn nnn SmI IIIIIT Teenan 19 Distillate oil emulsion ....-.--v---