INSECT PESTS OF OHIO SHADE AND FOREST TREES 273 



Control. Collecting the clusters of feeding caterpillars or 

 spraying with arsenicals are the approved control measures when 

 such are required. 



THE GIPSY MOTH 

 (Porthetria dispar Linn) 



It seems almost superfluous to state that the gipsy moth is one 

 of the two imported caterpillar pests against which the United 

 States Government and various state and local organizations of the 

 East have been waging such heroic efforts during the last 'few years. 



Europe is the original home of the species, but it was inad- 

 vertently introduced in this country about 1869 by Prof. Leopold 

 Trouvelot, a French naturalist living at Medford, Mass., who was 

 conducting some experiments in silk culture. During the course 

 of the work some of the caterpillars escaped, and from this start 

 the insect has become established in all the New England States 

 and some adjoining territory. 



Egg clusters of this insect were found in the spring of 1914 

 on stone shipped from the East to Bratenahl, Ohio, a suburb of 

 Cleveland. After its arrival, the stone had been built into a wall 

 and many of the egg clusters had become broken and scattered so 

 that every opportunity existed for the pest becoming established. 

 Through the prompt and effective service of the State Bureau of 

 Horticulture, the Bureau of Entomology of the United States De- 

 partment of Agriculture, the residents of Bratenahl, and the For- 

 estry Department of Cleveland, it seems that the pest did not 

 become established, since nothing has been seen of it in any stage 

 since the discovery and destruction of the egg clusters 4 years ago. 

 Other introductions might be made in time, and it is with the hope 

 that the pest may be recognized promptly and handled with similar 

 dispatch that the following account is given in considerable detail 

 and the illustrations in natural colors are used. 



Description. The reader is at once referred to Plate XLIV for 

 a general idea of the appearance of the different stages of this pest. 



The male moth is much smaller than the female and vastly 

 different in appearance. It has a slender body, is olive brown in 

 color marked with black and has a wing expanse of about 1% inches. 



The female is heavy-bodied, light cream in color with delicate 

 black markings and measures a little more than 2 inches across her 

 expanded wings. 



The eggs are nearly round, are light yellow and are deposited 

 in lots of a few hundred to a thousand each in flat, round or oblong 



