168 AGRICULTURAL EXPERIMENT STATION. 



by a silken thread, and burrow to a depth of from two to six 

 inches. They make a tough cocoon of buff colored silk interwoven 

 with earth, and in twenty-four hours turn into the chrysalis. 



The Chrysalis are light grayish brown and about half an inch 

 long. The male slender and provided with wing cases ; the female 

 larger and without wing cases. 



LIFE HISTORY. 



The eggs hatch about the time the buds on the apple trees expand. 

 The young worms feed upon the tender leaves, seeking shelter 

 within the expanding flowers or buds when the weather is wet or 

 cold. They eat holes in the leaves while young, but when older 

 devour the whole pulp of the leaf leaving only the veins and midrib. 

 Thej^ feed for about four weeks, and when plentiful so destroy the 

 foliage as to give the trees the appearance of having been scorched 

 with fire. They have done great damage to foliage trees along 

 highways. While letting themselves down to the gr ound they are 

 often swept off by carriages and carried long distances. 



The larva enter the ground, spin a cocoon, are converted imme- 

 diately into the chrysalis state, from which, during the fall, winter 

 and following spring they emerge in the perfect form, completing 

 the life history'. 



REMEDIES. 



Destroy the egg clusters when seen. Kill the moths when found 

 about the orchard. Jar the trees and destroy the larva that sus- 

 pend themselves b}' threads. 



Prevent the wingless females from ascending the trees, and the 

 larvae from descending or ascending. This ma}" be done by means 

 of stickv substances bandaged to the tree, by troughs filled with oil, 

 or b}' collars of metal, wood or glass fastened to the tree and slop- 

 ing downward like an inverted funnel. Among the siicky substances 

 that have been used are included tar mixed with oil, refuse molasses, 

 printer's ink, lard and sulphur and slow drying varnishes. The best 

 way to apply these is to put them on a strip of stiff paper or canvas 

 six inches wide tied by the middle around the tree a few inches above 

 the ground. 



Troughs can be made of rubber, tin or lead, and put around the 

 trunk and kept full of oil. A good collar can be made from a tin 

 band somewhat larger than the trunk, to the top of which is attached 



