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the wheat field was slight, and where so many grass-like weeds had 
sprung up in the wheat that they afforded food to the bugs in the 
field at harvest sufficient to detain them there for several days. There 
was virtually no migration on foot out of this field, the chinch-bugs 
generally lingering until the appearance of their wings enabled them 
to scatter by flight to more favorable breeding grounds. 
At Carbondale, where they were the most abundant, the corn ad- 
jacent to infested wheat was saved from all injury worth noticing, 
while the crop on some other fields in that region not protected, 
was completely destroyed for many rods inward from the edge of 
the field, and badly injured for a considerable distance further. 
The Carbondale Experiment. — On a farm situated one mile west 
of Carbondale, belonging to Mr. Robert Thorpe and referred to 
in this account as the Thorpe farm, was an irregularly shaped field 
of one hundred and forty acres of wheat which in June, 1904, was 
generally and considerably infested by chinch-bugs, sufficiently so 
to threaten notable injury to the wheat crop itself and the destruc- 
tion at harvest-time of much of the corn adjacent. Indeed, by the 
last week in June the wheat was ripening irregularly, turning 
brown in patches where the chinch-bug was most abundant, in ad- 
vance of the general ripening of the field, and from these patches 
the insects were already beginning to move into other crops. 
A corn field of twenty-seven acres cornered into this wheat at 
the northwest in such a way that the division line of the two crops 
micasured three hundred and seventeen yards on the east and three 
hundred and thirty-eight yards on the south, the remainder of the 
southern side being bounded by woodland. In the southwest cor- 
ner of this wheat was another field of corn of only four acres, so 
placed that it was bounded by infested wheat only on one side for 
about one hundred yards. A third field of corn, on an adjacent farm 
belonging to Ralph Thompson, was also exposed to invasion from 
the wheat field for a distance of about one hundred and forty yards. 
This corn was south of the wheat, from which it was separated by 
a roadway of the usual width. 
The situation here was complicated by the fact that in the north- 
west field of twenty-seven acres of corn a large pile of waste from 
a corn shredder had been left the preceding fall, in which quantities 
of chinch-bugs had passed the winter. Coming out in spring, many 
of these laid their eggs in the young corn, which thus became im- 
mediately infested from within by the first generation of the year. 
A part of the wheat bordering this field on the south had ripened 
early, owing perhaps to chinch-bug injury, and the bugs from this 
vicinity had already begun to invade the corn before our experiment 
