120 THIRD ANNUAL REPORT OF 



and when the proper time comes around again the eggs will hatch, 

 and the same cycle of changes takes place each year. 



This insect in all probability extends wherever the wild black 

 cherry ( Cerasvs st rotina) is found, as it prefers this tree to all others ; 

 and this is probably the reason why the young so often hatch out be- 

 fore (he apple bads burst, because, as is well known, the cherry leafs 

 out much earlier. Besides the Cherry and Apple, both wild and cul- 

 tivated, the Apple-tree Tent-caterpillar will feed upon Plum, Thorn, 

 Rose and perhaps on most plants belonging to the Rose family, 

 though the Peach is not congenial to it, and it never attacks the Pear, 

 upon which, according to Dr. Trimble, it will starve. It does well on 

 Willow and Poplar and even on White Oak, according to Fitch, who 

 also found it on Witch Hazel {Hamamclis) and Beech. 



REMEDIES. 



Cut off and burn the egg-clusters during winter, and examine the 

 trees carefully in the spring for the nests from such clusters that may 

 have eluded the winter search. The eggs are best cut off in the man- 

 ner presently to be described for the Tent-caterpillar of the Forest. 

 Though to kill the caterpillars numerous methods have been resorted 

 to, such as burning, and swabbing with oil, soap-suds, lye, etc., they 

 are all unnecessary, for the nests should not be allowed to get large, 

 and if taken when small are most easily and effectually destroyed by 

 going over the orchard with the fruit-ladder, and by the use of gloved 

 hands. As the caterpillars feed about twice each day, once in the 

 forenoon and once in the afternoon, and as they are almost always in 

 their nests till after a. m., and late in the evening, the early and late 

 hours of the day are the best in which to perform the operation. As 

 a means of facilitating this operation, it would be a good plan, as Dr. 

 Fitch has suggested, to plant a few wild cherry trees in the vicinity 

 of the orchard, and as the moths will mostly be attracted to such 

 trees to deposit their eggs, and as a hundred clusters on a single tree 

 are destroyed more easily than if they were scattered over a hundred 

 trees, these trees will well repay the trouble Avherever the Tent-cat- 

 erpillar is known to be a grievous pest. 



The chrysalids of this caterpillar are often found filled with little 

 maggots, which produce minute Chalcididan4-winged flies of metallic 

 green and black colors,* and belonging to the very same genus as 

 the celebrated Hessian-fly parasite. This parasite, with other canni- 

 bal insects, and perhaps more or less favorable seasons, tend to pro- 

 duce a fluctuation in the numbers of these caterpillars, so that they 

 are more numerous some years than others, and they were more nu- 

 merous in 1868 than they have been since. It has also been noticed 

 that dry summers are injurious to them. According to Dr. LeBaron, 



* Described as Cleonymus clisiocampcc by Dr. Fitch (Rep., vol. I, p. 200), but subsequently 

 more properly rei'erred to the genus Semiotellus (Rep., Vol. Ill, p. 141. 



