30 THE SPRING GRAIN-APHIS OR " GREEN BUG," 
early and the remainder later in the season the latest sown was very 
much more seriously damaged than that sown earlier. About the 
only portions of the early-sown part of the field to suffer serious 
injury were on the poorest soil. In short, the Toxoptera was found 
to be working its greatest damage in late sown or pastured wheat 
fields and among the young oats. Natural enemies were busily at 
work and apparently fast overcoming the pest. 
In the meantime Mr. Ainslie had found the pest destroying wheat 
in spots in the wheat fields about Fayetteville and Summers, Ark., 
March 16 to 20, as well as at Chandler, Okla., March 24, and at Guth- 
rie, Okla., on March 25. Near the latter place large circles were 
observed in the otherwise green fields of wheat. In the center of 
these circles the red soil was exposed by reason of the killing of the 
wheat plants, and these exposed circular areas were bordered by a 
band or girdle of yellow half-dead wheat plants, where the Toxoptera 
were most abundant. (See PL I, fig. 2.) In another field in this 
vicinity there was a stack of oats straw of the previous year, and from 
this stack a dead area extended at least 100 feet to the south. This 
area was nearly circular, with the stack almost in the center of the 
circumference. Xear and surrounding the stack was an area of dead 
volunteer oats, and beyond this a stretch of bare ground indicated 
where wheat had once stood. From people occupying a house near 
by something was learned of the previous history of this straw stack 
from which Mr. Ainslie determined that volunteer oats had sprung 
up after thrashing in 1906; these oats turned brown soon after, 
causing some wonder among farmers, and during the winter the plants 
died. The trouble spread to the wheat adjoining and here the wheat 
plants died early in the spring. There was here seemingly a repetition 
of the conditions in the fields about Summers, Ark., where Toxoptera 
infesting volunteer oats extended its destruction from these to the 
wheat near by. 
On March 26, between Guthrie and Kingfisher, Okla., Mr. Ainslie 
observed that the dead spots in the wheat fields were a striking feature 
of the landscape, for in the sunshine the bright green of the young 
grain made a striking contrast with the yellow-rimmed red circles 
where the Toxoptera had destroyed the wheat. Occasionally a field 
was free from these areas, but more of them were frightfully spotted 
in this manner. A field of wheat that was pastured more closely than 
most grain fields lay in the edge of Kingfisher and showed the attack 
of the Toxoptera worse than in adjoining grain. On March 27, at 
Kingfisher, Toxoptera was flying by the millions, the air being full of 
the migrants, and farmers who drove to town were covered on the 
windward side to their annoyance. The aphides seemed for the most 
part to fly low, but the wind hurried them at such a rapid rate that 
they might easily have been invisible when higher in the air. On the 
