EXPERIMENT STATION BULLETINS. 



133 



REMEDIES. 



Wlien the insect attacks fruit trees it can be kept in comparative subjection by the 

 use of winter washes. Prof. Comstock recommends* a winter wash of lime and sulphur, 

 using one-half bushel of shell lime to six pounds of powdered sulphur, and the 

 mixture brought to the consistency of whitewash with hot water. This should 

 be applied to all parts that can be reached. It is probable that other winter washes 

 in common use against scale-insects also will prove beneficial here. 



9. SOME INSECTS OF OUR SHADE TREES. 



It is often of as much advantage to know which insects are harmless as to know 

 which are injurious. Many insects are harmless for long periods of time and then, 

 some season when the conditions are right, they multiply to a surprising extent and 

 become, for a short time, serious pests, only to subside again quickly to their ordinary 

 number. A large number of insects are conspicuous and attract a great deal of atten- 

 tion, while the damage resulting from them is so slight that it is insignificant. Much 

 time and trouble are annually wasted in fighting insects that belong to this latter 

 class. To both of these classes belong manv insects working on shade and forest trees. 



10. LEAF-MINERS AND CASE-BEARERS. 



The leaves of shade and forest trees are often disfigured by patches of dead skin in 

 the form of blisters or blotches of various' shapes ; sometimes irregular in outline, 

 sometimes trumpet-shaped, and in other cases of all conceivable shapes and sizes. If 

 we look more closely into the matter, we find that there is a good deal of regularity 

 in the form and size of these blotches on any one kind of a tree, those found on a par- 

 ticular tree at a certain time usually being a good deal alike or belonging at most to 

 two or three different sorts. These mines or blisters are the dwellings of small insects 

 that live on the soft, succulent tissue found between the upper and lower surfaces or 

 skins of the leaf. Very small indeed must an insect be to find room to live in such a 

 place, but these little fellows do it, and sometimes congregate in such numbers as to 

 seriouslv afl'ect the trees. 



11. WHITE OAK LEAF-:\riXEn. 



[Lithocolletis cincinnatiella Clem.)* 

 All oak leaf-miner that multiplied to a surprising extent last summer is shown in 



Fig. 10. Oak Leaf-miner, Lithocolletis cincinnatiell'i. larvii and luijia. (Original.) 



Fig. 11, which represents the adult moth. The larva or gnih. an enlarged figure of 

 the head, and the pupal or resting stage, are shown in figure 10. 



* Kep. Ent. U. S. Dept. of Ayr. Is;i7, p.L'l-.'. 



* This inse(;t was kindly ileterniined by .Miss .Mary K. .Murtfeldt of Kirkwoud, .Mo. 



