ECONOMIC INSECTS OF THE YEAR IN OHIO. 71 



SOME ECONOMIC INSECTS OF THE YEAR IN OHIO. 



By A. F. Burgess, Columbus, Ohio. 



The most serious pests observed or reported during the year will be 

 considered under the following heads: Grain insects, orchard in- 

 sects, and forest and shade tree insects. Some remarks will also be in- 

 cluded concerning the mosquitoes of the State and a few other insects 

 that caused injury. 



GRAIN INSECTS. 



The yield of wheat in Ohio for the year 1905 was above the aver- 

 age, but the acreage sown was considerably reduced. Very slight 

 injury by the Hessian fly {Mayetiola destructor Say) was reported. 

 Late in June complaints were made in nearly all sections of the 

 State that the wheat heads Avere not properly filled out at the tip, and 

 most farmers attributed this condition to the " weevil," which is more 

 properly known as the wheat midge {Gontarinia [Diplosis] tritici 

 Kirby). 



Several samples received with crop reports sent to the Department 

 of Agriculture were examined, but no trace could be found of insects 

 or insect work. Apparently the grain in the tips of the heads had 

 failed to mature. On July 7 growing wheat near Columbus was ex- 

 amined and many heads found in this condition. Many of the straws 

 and leaves had been attacked by the wheat rust, and a considerable 

 number of plants were found which were injured by the work of 

 larvae of a species of Isosoma. Usually a hard spot was found be- 

 tween the second and third joint from the ground, which encircled 

 the stem, cutting oft' the sap, and light yellow larva? were found 

 within. 



Straws similarly infested were collected from shocks and stubble 

 in Wood, Ottawa, Erie, Fairfield, Miami, Montgomery, Franklin, and 

 Greene counties during July and August, which indicates that the 

 injury caused this year was quite general throughout the State. As 

 some farmers claimed that the actual amount of grain was from one- 

 third to one-half less than the prospective yield, it is evident that a 

 large loss resulted. 



Parasites that were bred from these infested straws Avere deter- 

 mined by Prof. F. M. ^Yebster as Etrpehnus allynii French, which is 

 a very common one, also a new species of Eupelmus and of Crypto- 

 pristus. The latter have not been described, but similar specimens 

 have been bred by Professor Webster during the present year. The 

 largest number of any of the parasites bred was of the latter species, 

 and it is undoubtedly of considerable importance as a natural check 

 of Isosoma. 



