X 



the other haud, was rare. From a correspondent in Carroll county 

 in the northern part of the State, I learned that these insects 

 have been so numerous there for several years as to compel the 

 replanting of most of the corn on sod. 



The practice of spraying apple-trees in spring to protect the 

 fruit from the codling moth, or apple worm, is now rapidly 

 becoming general, based largely in this State on the experiments 

 and recommendations of this office as published in our Bulletin 

 No. 1.* The results for 1887 were generally very encouraging, 

 but those for 1888 w^ere less decisive, owing to an extraordinary 

 scarcity of the insects themselves, especially in Central Illinois. 

 This was evidently due to the occurrence in 1888 of an unusual 

 apple crop following a season of unusual scarcity of this fruit. 



A new and peculiar insect observed by us for several years, and 

 known in the office as the burrowing web worm, occurs abundantly in 

 grass, and in corn after sod, not in numbers, however, so far as*now 

 known, to be a serious enemy to the latter crop. This species was 

 bred in 1888 to a moth, Pscudanaphora arcanella, described else- 

 where in this report. A less common species of similar habit was 

 also bred in 1888, and proved, to be a Csenogenes, described on 

 another page as C. morUpennella, Grote. 



The history of the Hessian fly during the past two years ex- 

 hibits anew the effect of drouth upon the multiplication of that 

 species. Many of the wheat tields of Southern Illinois in regions 

 which had been free from the fly the preceding year, showed it in 

 such numbers at harvest time in 1887 as to make it seem probable 

 that the following crop would suft'er heavily; but a severe mid- 

 summer drouth following, prevented almost entirely the growth of 

 volunteer grain, and very probably also dried up the larv^t^ and 

 pupae of the fly in the field. As a consequence, these neighbor- 

 hoods in 1888 were almost absolutely free from evidence of at- 

 tack, although in adjacent counties, where the drouth was less 

 severe, the fly was noticeably abundant in the fall of 1887 and in 

 the following spring. 



Experimental sowings in 1887 and 1888, made to trace the sum- 

 mer history of this insect, failed because of the drouth,— in the 

 former year completely, in the latter partially, — only the latest 

 planting growing. One plot, sown at Albion, Edwards county, 

 July 28, started slowly, and was heavily attacked by chinch bugs 

 and grasshoppers. There no Hessian flies were detected August 

 24, but by September 13, larvii) of almost all ages occurred in 

 great abundance, and by the 18th a few had formed fresh puparia. 

 Transferred to the office at Champaign and kept in the open air, 



"I'ho iiH-tliod of lif-ld ni)])lic!itioii now iuohI commonly used difT(>rH wtdoly from thai of my nuh- 

 li>ln (1 cxperiiiifiits In llic lattor, lln> liiifnt posnihle Hpr.-iy was by piiMHiiin tlio no/./lo nboiit 



ttirouL'h th«' f^Iiiip' of ilu' tree. In lli<> (ommoii orchard i)nictiiM' a miicli coarHcr i^pniy is thrown 

 from l)onealh, tlirou},'h a short tubo, witli Hiitlicicnt forco to r»'ach the lop of th(> tree after Icavlnj; 

 file uo/zhj. A ^'renter nmoniit of water boin;,' tliHH applied, a smaller proi)orlion of lln^ poison it< 

 necessary. More than r)no pound fo two hnndred ;;allon8 is snporlluoiiH, and iikiv injui ioii^. 

 w hereae in my own experimenlB we f(»(ind a pound to llfty {gallons harmlcHs. 



