4-H CLUB INSECT MANUAL 



27 



Figure 65.- 

 worm. 



-Boll- 



It is distributed 



reason why scientists assign a technical name to an insect. For in- 

 stance, Heliothis ohsoleta refers to the corn earworm or the cotton 

 bollworm, known to tomato growers as the tomato fruitworm. No 

 doubt many persons have seen this worm feeding 

 on the end of a roasting ear or chewing holes in 

 tomatoes ; others have seen it feeding in cotton bolls, 

 but probably few have realized that this worm is 

 the young stage of a fawn-colored moth which has 

 a wingspread of about iy 2 inches. These moths 

 have sucking mouth parts but cause no damage ex- 

 cept in laying eggs that hatch into little larvae. 

 The insects have complete changes in form during 

 the life cycle, and there are several generations each 

 year. They overwinter in the pupal stage in the 

 earth. This pest is possibly public enemy No. 1 

 among the insects attacking the food crops of man. 

 through temperate and tropical regions and attacks various kinds of 

 plants. 



Cutworms. — Practically everyone who has set out young plants has 

 noticed that within a day or so after planting some are cut off just 

 at the surface of the ground. Under such circumstances, a well- 

 informed person usually scratches a little 

 soil away from the remaining stump of the 

 plant and there finds a gray worm or larva 

 coiled and waiting for darkness so that it 

 can attack another plant. These larvae are 

 called cutworms. The parent is a night- 

 flying moth. There are a great many dif- 

 ferent kinds of cutworms. The markings 

 on the adults and larvae differ greatly. 

 The moths have four wings, the hind pair usually being paler in 

 color than the forewings. The wing expanse is about l 1 /^ inches. 

 Cutworms feed on many kinds of plants, and sometimes climb fruit 

 trees and injure them. They have a complete life cycle and there is 

 one generation a year. Eggs are usually laid in midsummer, and 

 the insects overwinter as partially grown larvae. Cutworms are 

 rather severe pests. The most common control measure is the appli- 

 cation of poisoned bait; however, stomach poisons sprayed on the 

 plants they are injuring will kill the climbing forms. The species 

 shown here is the moth of the spotted cutworm (Agrotis c-nigrum). 

 Eastern tent caterpillar.— Practically every spring, about the time 

 the apple and cherry trees, especially wild cherries, begin to leaf, 

 there appears in the crotches of the 

 branches a small webb which harbors a 

 young army of caterpillars. These little 

 fellows appear as if by magic and start 

 chewing the leaves off the trees. Some- 

 times they become abundant enough to 

 strip all the leaves off these trees. This 

 insect is called the eastern tent caterpillar 

 {Malacosoma americana) . Its parent is a 

 moth that flies around at night late in the 

 summer and deposits eggs in the branches 

 of certain fruit trees. The eggs do not hatch until the follow- 

 ing spring. The moths are reddish brown with whitish lines on 



Figure 



-Cutworm. 



Figure 67. — Eastern tent cater- 

 pillar. 



