INSECTS INJURIOUS TO AGRICULTURE. 211 



young larva upon the roots. It has been discovered that 

 the insect can continue propagating under ground for at 

 least four years without the laying of fertilized eggs. 



REMEDIES. In France and Southern Europe preventive remedies, 

 such as the submergence of the vineyards, and especially the importa- 

 tion and use of American stocks, have been the chief means of success 

 in dealing with this pest. The season, however, says Riley, in which 

 insecticides (especially sulpho-carbonates) applied to the roots will do 

 most good is in the interval between the hatching of the fertilized 

 winter-egg and the appearance of the winged females, i.e., during 

 May and June. 



Other insects occasionally injuring the vine are the larva 

 of the grape plume-moth (Pterophorus), which, as the leaves 

 and flower-buds expand, eats them, in certain years mate- 

 rially lessening the crop. Various other caterpillars, as the 

 "vine-dresser" (Everyx myroii), which cuts off the leaves 

 and sometimes the half-grown clusters of grapes (as does 

 also the tree-cricket), also certain leaf-beetles, do more or 

 less harm, while the fruit is at times infested by a leaf -roller 

 (Lobesia botrana), and the seeds are sometimes tenanted by 

 the little white maggot of a chalcid (Isosoma vitis), which 

 causes the fruit to shrivel, without maturing. 



Injuring Fruit-trees. 



Of insects injuring fruits, Mr. J. A. Lintner estimates 

 that there are in the United States at least 1000 species; of 

 these 210 are known to live at the expense of the apple-tree. 

 We can only call attention to some of the most pernicious 

 pests, referring the reader for further information to Mr. 

 W. Saunder's excellent book, "Insects Injurious to 

 Fruits." 



The Apple-tree Borer (Saperda Candida Fabr.). This 

 beetle (Fig. 102) flies about the orchard in May and June 

 in Missouri and Illinois, but in July in New England, 

 and the female lays its eggs in gashes in the bark. The 

 larva or grub upon hatching bores upwards into the wood, 

 where it lives within a few days of three years. Enlarging 

 its burrow, it transforms in a cell lined with chips, situated 



