REPORT OF THE STATE ENTOMOLOGIST I9O9 I9 



gipsy moth caterpillar, has materially reduced real estate values 

 ill some of the worst infested sections. 



Watch for the pest. The material injuries outlined above 

 emphasize the necessity of keeping a close watch for the ap- 

 pearance of this insect, to be followed by prompt repressive 

 measures if we Avould avoid extended losses. The Entomologist, 

 in past years, has sent out a warning placard illustrating this 

 insect and the gipsy moth in colors and giving the salient 

 characteristics of both species. These placards may still be 

 obtained upon application. A general publication [N. Y. State 

 Mus. Bui. 103J has also been prepared and will be sent to in- 

 terested parties. 



Salient characters. The moths are snow-white, brown tailed 

 insects with a wing spread of i^ to i^ inches. They are 

 abroad in early July, fly readily and may be carried consider- 

 able distances by favorable winds. 



The eggs are deposited in midsummer on the under side of 

 leaves, in patches covered by brownish hairs or scales. The 

 young caterpillars appear in August and feed for the most part 

 in the tops of trees. They occur by preference on wild cherry, 

 pear, apple, maple, elm and white oak, constructing a very 

 characteristic, close, firm web nest [pi. 22] differing greatly 

 from the loose, open nests inclosing many leaves, of the fall 

 webworms and easily distinguished from those of the common 

 tent caterpillar because they are at the tips of small limbs and 

 not in the crotches. 



The brown tail moth caterpillars winter in firm nests inclos- 

 ing a few leaves and invariably at the tips of twigs. Conse- 

 quently, winter is one of the most favorable seasons for the 

 detection of this pest. We would urge every one residing in 

 a locality liable to infestation, to keep a close watch for the 

 presence of these characteristic winter nests. 



The nearly full grown brown tail moth caterpillar, found 

 only in late May and early June, is about an inch long, a bright 

 tavvmy or orange-brown color, with a conspicuous row of white 

 spots on either side and two bright red spots on the back near 

 the posterior extremity. 



Experimental work. The following experiments with hydro- 

 cyanic acid gas were conducted during the winter and early 

 spring, in an effort to find a reliable method of freeing nursery 

 stO'ck from any caterpillars which might escape the inspector's 

 eye. The larvae used for experimental purposes were obtained 



