208 



DESTRUCTIVE INSECTS. 



The Strawberry Leaf-roller (Phoxoptcris comptana} is in 

 many localities the most injurious insect pest of the straw- 

 berry. A small greenish or brownish caterpillar folds the 

 leaflets of the strawberry by bringing the upper surfaces to- 

 gether and fastening them by silken cords (Fig;. 276). In this 

 retreat the insect spends its whole larval life, feeding upon 

 the leaf, and ultimately causing it to turn brown and shrivel 

 up. The transformation through the brown pupa to the adult 

 insect a pretty little brown moth takes place within the 

 folded leaf. There are two annual broods of the pest in the 



FIG. 276. Strawberry Leaves Folded by the Strawberry Leaf-roller. 



North, and at least three in Kentucky and southward. The 

 winter is passed as a pupa in the rolled leaves. 



Spraying with poisonous mixtures is impracticable while 

 there is fruit on the plants, and experiments indicate that 

 such applications are not very effectual at any time, so se- 

 curely protected are the feeding-grounds of the caterpillars. 



However, it is claimed that the pest can be almost exter- 

 minated in a field by mowing it after the crop is gathered, and 

 after leaving it a day or two to become dry, burn it over, per- 

 haps with the aid of a little straw or rubbish. This can usually 

 be done without the slightest injury to the plants. This will 

 destroy the leaf-roller as well as several other kinds of insects, 



