SOME INSECTS INJURIOUS TO ORCHARD FRUITS 563 



in hope that they may ultimately be as effective in this country 

 against both the brown-tail and gipsy moths. The most effective 

 natural check of the brown-tail caterpillar is a fungous disease 

 which often completely de- 

 stroys large colonies, both in 

 the spring and fall. 



Control. On fruit and shade 

 trees the winter nests may 

 be pruned off and burned in 

 winter, thus preventing any 

 injury the next spring, but 

 this is impracticable on forest 

 trees, which as a rule are not 

 seriously injured. The re- 

 peated pruning often injures 

 the trees, as it is d fficult 



T 



to cut all the nests without 



removing more of the new 



growth than is desirable. It 



is better, therefore, to spray 



the trees with arsenate of lead, 4 pounds to the barrel, as soon 



as the eggs hatch in late summer, and thus destroy the young 



larvge before they have spun their winter webs. 



FIG. 415. Young caterpillars of the 

 brown-tail moth skeletonizing an 

 apple leaf in late summer. 



The Gipsy Moth * 



History. The Gipsy Moth has been known as a serious insect 

 pest in Europe from the time of the earliest naturalists, the first 

 authentic record being in 1662. It extends throughout the 

 continent of Europe, over much of Asia and into Northern Africa, 

 but is chiefly injurious in central and eastern Europe. It fre- 



* Porthetria dispar Linn. Family Liparidce. See Forbush and Fernald, 

 "The Gypsy Moth," Mass. State Board of Agr. (1892); L. O. Howard, 

 -Farmers' Bulletin 275, U. S. Dept. Agr.; Annual Reports of the Mass. Super- 

 intendent for the Suppression of the Gypsy and Brown-tail Moths; E. D. 

 Sanderson, Bulletin 136, N. H. Agr. Exp. Sta.; Rogers and Burgess, Bulletin 

 87, Bureau of Entomology, U. S. Dept. Agr., containing bibliography. 



