7 
timothy meadows and even in bine grass pastures, breeding as 
rapidly there, to all appearance, as if these fields had been in 
wheat. The oats especially were suffering everywhere, bugs of 
all ages being equally dispersed throughout the fields*; and, later, 
corn fields w r ere invaded in the usual way, first from the edges, 
and then by a general flight. In short, it was difficult to believe, 
after a careful examination of this neighborhood, that the chinch 
bugs w r ould have been any more abundant if every other 
field had been in wheat; while it seemed probable that if a mode¬ 
rate amount of wheat had been sown, this would have received 
the weight of the attack and the other crops would have been 
correspondingly relieved.f 
RELATIONS OF THE AREA OF WHEAT AND OTHER 
CROPS TO CHINCH-BUG INJURY. 
The fact (now to be clearly seen in Illinois) that chinch bugs 
■will breed in winter wheat as well as in the spring varieties,, and, 
under certain circumstances, in oats and timothy scarcely, if at 
all, less freely than in wheat, tends greatly to. unsettle the ideas 
of the entomologist and to confuse the practice of the farmer, 
especially as we lack authentic detailed evidence on the relation 
of wdieat and other crops to chinch-bug increase, drawn from a 
territory large enough to warrant positive generalization. I have 
consequently thought it highly important that an extended and 
thorough-going study should be made of the relations of the cul¬ 
ture of wheat (and indeed of oats, corn, and grass likewise) to 
chinch-bug injury to the various crops. 
Conditions in Illinois during 1887 were as favorable to the in¬ 
vestigation of this subject as it would have been possible to 
arrange, since we had coincident every variation in chinch-bug 
damage, from none whatever to the complete destruction of every 
crop liable to attack, and also every variation in wheat culture, 
♦ The marked preference for wheat where both wheat and oats are accessible to the chinch bug 
was very clearly demonstrated by an observation which I made in Washington county in 1886. In 
a field sown partly to each crop, with no fence between, chinch bugs were thickly clustered on the 
stems of wheat, especially on the nodes, up to the very boundary line, but not one could be found 
on the other grain. Even where the two were intermingled, the stalks of wheat among the oats 
had been carefully sought out, while the oats plants among the wheat were as generally avoided. 
tOf especial interest in this connection is the following letter written May 14,1887, by Hon. J. 
W. Robison, Towanda, Kansas, a former resident and large fanner of Illinois and an ex-senator of 
this State: 
“The old chinch bugs,—those of last year's crop that have wintered over,—are now extremely 
numerous and destructive here; as numerous as I ever saw them in August and September in the 
mature form. They have already entirely destroyed the wheat on thin soil and half of that on our 
best lands. They have also destroyed at least half the oats crop, and, strange as it may appear, have 
killed a few patches of corn and are distributed over all our corn, from a few to fifty on a hill, the 
corn being from one inch to six inches in height. They are laying a very large crop of eggs on all 
these plants, but none have yet hatched. Our wheat is just heading out,and some heads are in blos¬ 
som. This is the first time I have known old, last year’s bugs to lay very many e^gs on young 
corn. Timothy and orchard grass are very dry and small, but not harmed by the bugs. 
