INSECTS INJURIOUS TO ORCHARD FRUITS 499 



trees in early spring, particularly in old sod 

 orchards which have not been 

 cultivated or sprayed. 



The Spring Canker Worm* 



This species is so called from 

 the fact that its eggs are laid 



in the early spring instead of in the fall, as are 

 those of the other species. It occurs from Maine 

 to Iowa and southward to Texas, and in Colorado and 

 California, but has not been reported on the Atlantic 

 Coast south of New Jersey according to Coquillet. It 

 seems to be particularly injurious in the Mississippi 

 Valley. The full-grown caterpillar is from three- 

 quarters to one inch long, slender, and cylindrical, 

 and has no prolegs on the middle of the abdomen. 

 The color varies from ash-gray to green or yellow, 

 but the predominating color is dark greenish-olive 

 or blackish, marked with narrow pale lines down the 

 back and a whitish stripe along each side. The wings 

 of the male moths expand an inch, and are semi-trans- 

 parent, brownish-gray, with three rather indistinct dark 

 lines across the fore-wings. The females are wingless 

 and at the first glance look much more like spiders than 

 moths. They are about one-third inch long, of a dull 

 brown or grayish color with a dark brown stripe down 

 the middle of the back. 



Life History. The moths emerge from the pupae in 

 the ground in March and April and the females climb 

 up the trunks of the trees, where they place their eggs 

 in irregular masses of about fifty, under loose scales of 

 bark, in cracks in the bark, in crotches of limbs, etc. 

 The individual eggs are yellowish-green, turning quite 



FIG. 422. Canker worms dropping from foliage in characteristic attitudes. 



(After Bailey.) 



dark just before the larvae hatch, of an oval shape, and about 

 one-thirty-fifth inch long. The eggs hatch in about a month and 

 the young caterpillars commence to feed on the leaves just as they 

 * Paleacrita vernata Peck. Family Geometridoe. 



