SHADE TREE INSECTS 51 



larvae are appearing, about 3 weeks later, at which time the tree will probably 

 have all its foliage and the entire leaf surface may be poisoned. This is normally 

 in early June. Lead arsenate is recommended in the proportion of 5 pounds to 

 100 gallons of water with lli pints of fish oil or raw linseed oil added as a sticker. 



Because the mature larvae, or grubs, go to the ground to pupate, both grubs 

 and pupae may often be found in clusters near the base of the trees during periods 

 of heavy infestation. These larvae and pupae may be destroyed by pouring hot 

 water or carbon disulfide over them. Care should be taken to see that the mate- 

 rial does not come in contact with the trunk or roots of trees or any other culti- 

 vated plant which might be injured by such an application. A much safer mixture 

 would be 1 pint of nicotine sulfate with 4 pounds of laundry soap to 100 gallons 

 of water. Occasionally it might be feasible to crush or collect and drop the insects 

 into a can of kerosene and water. Another method falling into this category is the 

 destruction of any groups of hibernating adults which might be found in shelters 

 near infested elms. 



It should be remembered, however, that these are merely' intended to supple- 

 ment the all-important spraying measures by helping to reduce the future gen- 

 eration of destructive grubs and beetles and should not be solely depended upon 

 for control. 



Britton, \V. E. Conn. Agr. Exp. Sta. Bui. 155. 1907. 



Britton, W. E. Conn. Agr. Exp. Sta. Circ. 84. 1932. 



Felt, E. P. N. Y. State Mus. Mem. 8(1) :146-155. 1905. 



Felt, E. P. Jour. Econ. Ent. 27 (l):195-200. 1934. 



Fernald, H. T. Mass. Agr. Exp. Sta. Bui. 125:50-51. 1908. 



Herrick, G. W. Cornell Univ. Agr. Exp. Sta. Bui. 333:491-507. 1913. 



Howard, L. O. Jour. Econ. Ent. l(5):281-289. 1908. 



Mackie, D. B. Calif. Dept. Agr. Mo. Bui. 16(5) :294-301. 1927. 



Mackie, D. B., and Haenggi, C. Calif. Dept. Agr. Mo. Bui. 22:346-350. 1933. 



McDaniel, E. I. Mich. Agr. Exp. Spec. Bui. 243:6-9. 1933. 



Japanese Beetle 



Popillia japonica Newm. 



The Japanese beetle is a native of the Orient and was first found in this country 

 near Riverton, N. J., in 1916. Since then the insect has spread rapidly over a 

 large part of New Jersey and adjoining states as well as a considerable portion of 

 southern New England. It has proved to be a very serious pest. The larvae, or 

 grubs, feed on the roots of various plants and grasses. The adults feed on the 

 foliage of numerous fruit and shade trees, shrubs, garden plants, and field crops, 

 and also attack flowers and fruits. In feeding on the foliage they avoid the veins, 

 giving the leaves a skeletonized appearance. Among shade trees they especially 

 prefer elm, chestnut, horsechestnut, linden, and sassafras, but also feed on Nor- 

 way maple, pin oak, plane trees, Lombardy poplar, willow, and birch. When 

 preferred trees are not available, the beetles may attack the more tender foliage 

 of trees normally not touched. Conifers are seldom attacked. The beetles prefer 

 to feed on the parts of the plants exposed to the direct sunlight, beginning their 

 attack usualh' on the upper and outer parts of the trees and working downward 

 and inward. 



Description. The beetle is approximately }A, inch long, broadly oval in shape, 

 and shiny green in color. The wing covers, which are a coppery brown, do not 

 quite reach to the tip of the abdomen. Just beyond the edge of the wing covers 

 are twelve tufts of hairs which distinguish this beetle from other species which 

 it resembles. 



