GYPSY AND BROWN-TAIL MOTHS AND THEIR CONTROL 13 



Class 4. — Species that are unfavored food for gypsy moth larvae 



Arborvitae Huckleberry, highbush 



Arrowwood Inkberry 



Arrowwood, maple-leaved Juniper, common 



Ash, black Kentucky coffeetree 



Ash, blue Lambkill (sheep laurel) 



Ash, red Locust, black 



Ash, white Maple, mountain 



Azalea, white and flame Maple, striped 



Balsam, fir Mountain-laurel 



Blackberry, high Mulberry, red 



Blueflag, larger Mulberry, white 



Catalpa, hardy Osage-orange 



Cornus Osier, red 



Cranberry tree Pepperbush 



Currant, red Persimmon 



Cypress, bald Poison-ivy 



Dangleberry Privet 



Dock, narrow Raspberry 



Dogwood, flowering Sarsaparilla 



Elder, American Skunkcabbage 



Eubotrys, swamp Spicebush 



Feverbush Sweetbrier 



Grape Sweet pepperbush 



Greenbrier Sycamore 



Hackberry Tea, Appalachian 



Hardhack, pink Tuliptree 



Hardhack, white Viburnum, sweet 



Holly, American Walnut, black 



Honeylocust Willow, bay-leaved 



Honeysuckle, bush Winterberry, smooth 



MEANS OF SPREAD 



Egg clusters of the gypsy moth deposited on trees, lumber, stone, 

 and other products that are likely to be shipped may be carried long 

 distances and cause new colonies of the insect to be established. The 

 only way to prevent spread of this kind is to inspect such products and 

 treat any clusters found on them before they are shipped. 



Larvae of the gypsy moth may be carried on such moving objects 

 as trains and automobiles. Horse-drawn vehicles and freshets may 

 also transport them for limited distances, and egg clusters on debris 

 may be carried by high water. The danger of such spread is depend- 

 ent upon the extent of infestation along railroads, highways, and 

 streams. 



It is probable that the principal agent in the spread of the gypsy 

 moth is the wind. The chief trend of spread of the insect, since its 

 introduction into New England, has been to the north and northeast, 

 which is the general direction of prevailing surface winds after the 

 hatching season. 



Since the newly hatched larvae are abundantly supplied with hairs, 

 they are easily carried by the wind. Probably few larvae are ever 

 blown loose from their supports by the wind. An enormous number, 

 however, spin down from tree tops when disturbed and are intercepted 

 by air currents ; the strand of silk is broken and they are whirled away 

 with this silk attached to their bodies. Spinning larvae normally 

 sever the strand of silk by biting only when they come to rest upon 

 some object; they seldom do this while hanging free. The distance 

 that a larva may be carried aloft by currents of air depends to some 



