252 EXPERIMENT STATION KECORD. IVul. 41 



Experiments with poison baits against grasshoppers, D. A. IIickkk {Jour. 

 Econ. Ent., 12 {I'Jl'J), No. 2, pp. l'JJi-200). — This is ii report of experiments con- 

 ducted in the vicinity of Jauesville, Wis., where the red-legged locust, Mclanoplus 

 atlanis, and M. hivitattus occurred in greatest numbers and nearly all were 

 almost mature at the time of the experiments. 



In the tests of the attractiveness of different baits based upon the standard 

 formula, apples and bananas when used alone or with molasses were as at- 

 tractive as, or slightly more so than, lemon fruit or lemon extract. Apples and 

 molasses gave practically the same results as lemon fruit and molasses, while 

 lemon fruit and salt gave practically the same results as molasses and salt, but 

 both were slightly less effective than the first two combinations. Salt alone 

 seemed to give slightly better results than molasses alone. In all cases bananas 

 showed as good results as lemon fruit and seemed to give a heavier early 

 mortality. 



In determining the period of attractiveness of different fruits, it was found 

 that citrus fruits become flat within a day or two after application, whereas 

 the noncitrus fruits increased in odor and attractiveness as fermentation pro- 

 gressed. It was found that the young hoppers responded better toward the more 

 odorous bait. 



In tests of the comparative value of different arseuicals it was found that 

 wherever crude arsenious oxid was used in a direct comparison with Paris 

 green, as was the case in 6 exi>eriments in which applications covered approxi- 

 mately 65 acres, very little choice could be found, both working with nearly the 

 same rapidity and being eciually effective. Calciiun arsenate used in 4 ex- 

 periments in direct competition Avitli both Paris green and crude arsenious oxid 

 gave equally as good results. The addition of lemon extract to the standard 

 formula made a much more odorous bait and proved effective at the usual rate 

 of application, wiiile the standard bait used at the rate of from 6 to 8 lbs. per 

 acre gave eflicieut results. It is pointed out that the rate of application ap- 

 pears to depend upon the infestation and attractiveness of the bait. 



Grasshopper control in Kansas, G. A, Dkan, E. G. Kelly, and A. L. Fokd 

 (Jour. Econ. Ent., 12 {11)10), No. 2, pp. 213-217, pi. 1).—A brief report of work 

 carried on during one of the worst grasshopper outbreaks in the history of 

 Kansas, which took place in the summer and fall of 1918. 



Palmodes praestans and its prey, A. N. Caudell {Proc. Ent. Soc. Wash., 21 

 {1910), No. 2, p. JfO). — (Jupnohotcs fuUginosus, an orthopteran, is said to have 

 been captured by P. prwstans, a wasp which is scarcely one-third the lengtli 

 of its prey. 



Leaf hoppers injurious to apple trees, F. H. Lathrop {New York State Sta. 

 Bid. Jf5l {lOlS), pp. 185-200, pU. 4, flU'i- 2). — Among the serious insect enemies 

 of the apple in New York State are the three species of small leaf hoppers 

 here reported upon by the author, namely, the apple leaf hopper, Empoasca 

 iinicotor, and Enipoa rosw. 



Contrary to certain recorded observations the apple leaf hopper, of which 

 two generations were observe<l, hibernates largely, if not exclusively, in the 

 adult stage. On the other hand, E. unicolor spends the winter in the egg stage 

 and is single brooded ; E. ro-scp overwinters in the egg stage, largely on roses, 

 although a few eggs are placed on apples, and has two generations. These 

 species differ considerably in feeding liabits, the ai>ple leaf hopper obtaining 

 its food almost exclusively on tender terminal growth and causing a character- 

 istic curling of the foliage, while /:;. rosw and E. unicolor feed largely on 

 older leaves and may be found on young and older apple trees, E. rosw being 

 more abundant on older trees and E. unicolor on the younger trees. The leaves 

 attacked by these two species display white stippling on the ui>per surfaces. 



