"Prepared by the Clemson University Cooperative Extension Service's Entomology -- Plant Pathology and Agricultural Communications Sections, Federal Extension Service Cooperating.""Picture sheet no. 20.

Thomas, George W.

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r PS ee- 20 I . 4. 7. TOBACCO WIREWORM VEGETABLE WEEVI L Upper· Larva Lowor • Adult LOOPER TOBACCO INSECTS An Aid to Identification and Control 2. CUTWORM 3. HORNWORM 5. 8. BUDWORM Left · Damage to Leaf Right · Damage to Bud APH IDS 9. b. FLEA BEETLE Upper · Damage and Adult Lower · Adult SNOWY TREE CRICKET PREPARED BY THE CLEMSON UNIVERSITY COOPERATIVE EXTENSION SERVICE'S ENTOMOLOGY • PLANT PATHOLOGY ANO AGRICULTURAL COMMUNICATIONS SECTIONS, FEDERAL EXTENSION SERVICE COOPERATING Tobacco Insects An Aid To Identification And Damage George W. Thomas, Extension Entomologist 1. Wireworms, che larvae of several different species of click beedes, cause injury co newly ser tobacco plants by feeding upon the t<>ots and boring into the underground stem. Stem in1ury frequendy results in sconcing or plant death . Wireworms are slender, round , or slightly flattened. yellowish~brown to deep reddish-brown in color, from~ to an inch or more in length whtn full grown, and are slick and cough to the couch. Depc:ndins upon rhc species, it requires from one co three or more years ro complete a single genera-ricm. Tobacco following csrnblishe<l grasses, corn, or tobacco is mosr apt to he injur'-d by wireworms. 2. Cutworms, rhc larval stage of several species of moths, feed by chewing or cutting off leaves or entire plants near or slightly below rhe soil surface. Such injury can occur wichin tht: plane beds , but more often occurs within a few days following transplanting. Most feeding occurs ac night. During the day, the worm can Ix· found ro lled or coiled in the soil near the damaged plant. Depending upon the species, the larvae may be rc<ldish-~ray co grayish-black in color and arc about rwo inches in length when full grown. Cutworms may ovcrwi nccr as parcially grown larvae or batch from eggs liud by emerging or migraring moths in the: earl~, spring. There may be one or cwo gcncm1rions each >•ear. 3. Hurn worms, the: larval stagl· of either of cwo species of Sphi me moths, may consume large areas of leaf tissue during chc summer months. Both r:he romaro and tobacco hornworms will readily feed upon tobacco, bur it is the larrer specits which most commonly attacks Missouri tobacco. Female moths deposit their grcenish-pt-arl colored c:ggs singly on the underside of leaves. The eggs hatch in a few days into the t iny hornworm larvat: which begin their feeding upon leaf tissue. Abour four weeks are required for the bornworm larva co complete its growth, at which rime ic is about three incht:S in length. The macure larva pupates within the soil, and two ro three weeks lacer the adult moth emerges. There are cwo generations each rear. 4. Vegetable weevils arc nor found within the central and northwest Missouri robacco producing areas, but the pest is known w occur in rhe southern rier of counties bordering Arkansas. Boch the adults and the greenish-gray larvae may cause foliage damage in plant beds and on cransplanrs. 5. Budworm and corn earworm, the larva of two closely relaced species of moths, cause injury by chewins upon the leaves and wirhin rhe buds. Color vark-s from green to can to red-brown with longi-tudina l stripes on the top and on both sides. Both species may be present from mid co late season growing stages. The feeding of small larvae within the folded bud leaves results in holes and distorted leaves. The larger larvae feed upon maturing leaves, often consuming large areas oflcaf surface. There are usually two generations each year damaging robacco. 6. Flea beetles c:ausc injury by chewing small holes in the leaves on the lower portion of the plants. The adulrs overwinter .iround field margins and move into plant beds o r newly tr-ansplated fields. The adult is a very small, brownish-black. jumping beetle. Eggs are depositcd in che soil around the plants, the larvae feed upon tht: smaller roots, and the pupal stage is in the soil. There arc· two or more generations each year. 7. Cabbage looper, and possibly ocher species of loop-ers, cause tfamage by chewing ragged or irregular shaped holes in the kavcs . The larv.ieare I ight grten in color w1rh numerous \vhire lines running the lengrh of the boJy. The body ~radually capers toward the head . They crawl with a looping or measuring worm movement. Larva" nre usually found on che underside of the leaves. Then· arc several generarions each year, but mosr of che problems occur during the early summer. ' 8. Aphids, particularly rhe green peach aphid, cause damage by sucking sap from the leaves. Injury may appear as a shorcugc of nutrients accompanied by a downward rolling or puckering, and evenruall)• a chaffy leaf. These small. light greenish-yellow insecrs are found in colonies on the underside of the leaves. Boch winged and winsless forms are asexual and bear their young alive. There are many generations each year. For some unknown reason. this pesc has not, as yec, become a serious problem on Missouri tobacco. 9. Tree crickets, othc:r species of long-homed gra11/xippm, and 1r11e grasshoppm cause damage by chewing holes in the leaves. The adulr tree cricket is pale greenish-whice in color with a body about one-half inch in length. Besides their chewing damage, the · adulr female dc.•posits eggs in the midrib, often resulting in leafbreabge from winds. This group of insects moves intc> robacco from the surrounding vegetation. • Issued In furtherance of Cooperative Extension Work Acts of May 8 and June 30, 1914 In cooperation with the United States Department of Agriculture. Leonard C. Douglas, Acting Director. Cooperative Extension Service, University of Missouri and Lincoln University. Columbia, Missouri 65211 . • An equal opportunity institution. Archivversion -- Se extensn.missouredu

Tobacco insects : an aid to identification and damage

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