744 ANNUAIi REPORT OF THE Off. Doc. 



any part of the stalk, but in small plants are usually at or near the 

 surface of (be ground, where the tissue of the vine is hardest, and 

 the chances of retaining the form unaltered through the winter are 

 greatest. The beetles mature in August and September, and re- 

 main in the vines all winter." 



Concerning remedies, he saj^s: ''It is at once obvious that insecti- 

 cides are of no use in this case, because the larva is an internal 

 feeder; but its habit of passing the winter in the dead vines gives 

 us complete control over it. Simply rake up and burn all the vines 

 after the crop is gathered, and with them the entire brood of insects 

 will also be destroyed. Besides this, war should be waged against 

 the Jimpson weed and the horse-nettle, as otherwise a considerable 

 number of specimens will be likely to survive. If the presence of 

 larvae is noticed in the field, the only thing to be done is to stimulate 

 plant growth to the utmost by the application of appropriate and 

 readily soluble fertilizers, that the vines may be enabled to mature 

 the crop despite the attacks of the insects." 



White Grub. — The unsightly appearance of potatoes is due often- 

 times to the grubs of the May beetle. Growers seek a direct remedy, 

 believing that the application of some material to the soil should 

 destroy them. Station and farm tests have been very thorough in 

 this matter, and it may be stated confidently that no treatment of 

 the soil with insecticides will be effective unless the insecticide is 

 used at very heavy expense and in such large quantities that crops 

 would be destroyed. It is common to read of success from applica- 

 tions of common salt, kainit and other materials, but the disap- 

 pearance of the grubs was due not to the application given but to 

 the fact that the time had come for transformation to beetles. A 

 little study of the life history of the May beetle will make this fact 

 plainer, and will enable the grower to evade loss in some degree. 

 The beetles appear in May or early June, living on the foliage of va- 

 rious kinds of trees. Their eggs are deposited only among the roots 

 of grass, and the grubs hatch in July or August. These grubs con- 

 tinue in the soil for two or two and a half years, when they change 

 into a dormant form, and appear as beetles three years from time the 

 eggs were deposited. The grubs in the first autumn of their lives 

 are small, and the injury to crops by them is usually slight. In their 

 second summer they are voracious feeders, and likewise in their third 

 summer. I believe that they sometimes continue to eat until late fall 

 the third year, not changing to dormant form until spring. It is 

 quite common to find two broods of the May beetle in the same place, 

 and there may be three, giving grubs of all ages and sizes. When 

 such is the case, the ground becomes practically worthless, if each 

 brood of beetles is large. Usuallv there is onlv one brood that is im- 

 portant, and this gives a chance for some evasion of their injury. 



