INSECTS INJURIOUS TO THE GRAPE 455 



mentals as Spiraea and Deutzia, while it frequently injures the 

 blossoms of apple, plums, cherries and peaches, and when very 

 abundant will attack various vegetables, grasses, and grains. 

 The species occurs commonly from Canada to Virginia and Tennes- 

 see and westward to Colorado, and in Texas and Oklahoma, but 

 seems to do but little damage west of the Mississippi, being most 

 injurious in the Middle States. It is particularly destructive 

 where there are areas of light sandy soil grown up in grasses and 

 weeds, upon the roots of which the larvae feed. 



Life History. After feeding three or four weeks the beetles 

 suddenly disappear. During the middle of June, in New Jersey, 

 the females lay from 12 to 20 eggs, depositing them in the soil 

 singly. These hatch in two to three weeks and the larvae feed 

 on the roots of various grasses and possibly weeds and other 

 vegetation. They become nearly full grown by fall, when they 

 go below the frost line and hibernate over winter. The larva 

 looks very much like a small white grub, which it closely resembles 

 in every way, and is about three-quarters inch long when full 

 grown (Fig. 381, 6). In the spring the grubs come near the 

 surface of the soil and enter the pupa stage, which lasts from ten 

 to thirty days according to the temperature. There is but one 

 generation a year, and the injury is done by the beetles during the 

 three or four weeks they are abroad. 



Control. When the beetles are very abundant the only satis- 

 factory method of control is to pick them by hand or jar them 

 from the vines onto frames from which they may be collected. 

 In jarring, an umbrella-shaped frame covered with canvas or, 

 preferably, oilcloth, which slopes to a can of kerosene at the 

 bottom, is often used, being somewhat similar to that used for 

 the plum curculio. This is held under the vines and they are 

 sharply jarred or shaken, when the beetles will drop to the 

 frame particularly in early morning. Handpicking into a can of 

 kerosene and water is probably the most common method, how- 

 ever. Where the beetles are not excessively abundant they have 

 been controlled in some cases by thorough spraying with arsenate 

 of lead, 5 to 10 pounds per barrel, preferably applied with Bor- 

 deaux mixture, and recent experiments of the N. Y. Agricultural 

 Experiment Station with 5 pounds of arsenate of lead and 12 

 pounds of glucose per barrel gave excellent results. The num- 



