t' 
IN EXPERIMENTAL SOWINGS. 
0 ji, ' 
For the purpose of securing more precise and complete data 
concerning the midsummer history of the fly in Southern Illinois, 
I selected for experimental midsummer sowings a field near Edge- 
wood, in Effingham county, belonging to Mr. J. Lundberg, and 
one belonging to Mr. Aaron Young, at Billett Station, in Law¬ 
rence county, both of which had been too badly damaged by the 
fly to repay harvesting. These were, in fact, the only fields I 
was able to find in Illinois where the damage was last year suf¬ 
ficient for my purpose. 
The Lawrence County Field.— The history of this field was 
thus reported to me by the owner. It bore its first wheat in the 
summer of 1885—an excellent crop, showing no sign of the fly at 
any time. After harvest, the stubble was plowed between the 
5th and 10th of July, and considerable volunteer wheat sprang 
up which became badly infested by the fly. This wheat was 
allowed to stand until the last week in Octobev , when the 
ground was sowed again to wheat, put in with a double-shovel 
plow. This grain started well, but became, notwithstanding, some¬ 
what infested with the fly that fall (1885), and May 1 of the 
following spring was seen to be badly damaged. On the 15tli 
May, 1886, it contained great numbers of naked larvae, with a 
few freshly formed puparia. From these larvae, transferred to 
our breeding cages, we obtained several imagos May 28, and June 
8 and 17. The wheat was so badly damaged that it was not 
harvested, but was plowed up in June and the ground planted injj 
part to melons and in part sowed to wheat for my experiments.* 
1"our successive experimental sowings were made for me by Mr. 
Young, on lots each about one rod wide and ten rods long, the 
stubble being each time plcuvecl for the purpose immediately before 
sowing. The first, made July 13, 1886, came freely, but was soon 
nearly all killed by a violent attack of a new, third brood of the 
wheat bulb worm, Meromyza americana —as detailed elsewhere. 
Enough remained, however, to afford a sufficient temptation to any 
flies that might be abroad in search of a place of deposit for their 
eggs. The second sowing, made July 28, suffered like the first. 
Between these two sowings, a ueigfiboriiig Jfielcl of wheat stubble 
was plowed, and soon produced a good growth of volunteer wheat, : 
which was of great use to us later. 
The third and fourth sowings, made August 5 and 19, grew well, j 
and received no damage until attacked by the fly. 
* In a field adjacent, sowed October 10—much earlier, that is, than the infested wheat—no fly' 
appeared either in fall or spring, but the grain was headed finely May 15, and ultimately made a 
good crop. It seems highly probable, therefore, that the flies which deposited their eggs in the 
later wheat came only, or chiefly, from the volunteer wheat in the fall of 1885, and that if these had 
been killed by complete and timely destruction of the volunteer wheat itself, the subsequent dam^ 
age would have been prevented It is also apparent that the remarkable fact of the destruction of 
the late sown wheat, while early sown wheat beside it escaped, is to be similarly accounted for In 
the volunteer Avheat the fly passed "the period of early frosts in the relatively hardy state of larva 
or puparium, emerging later as the delicate and susceptible winged imago, and finding time be-i 
tween frosts to deposit its eggs in the young grain amid which it came to light. 
