19 
AGE TO SMALL GRAIN AS COMPARED WITH THE AREA IN WHEAT 
AND OTHER CROPS. 
erhaps the most difficult, and certainly the most interesting, 
lificant, and conclusive part of this discussion relates to the in- 
nce of wheat culture on damage to wheat itself and to oats by 
first brood of the bugs, under the two widely contrasted sets 
:onditions found in Centra] and Southern Illinois respectively, 
887. Certainly if it shall appear that the ratio of damage to these 
).s increased with increase in the areas of the crops themselves,—if, 
ther words, the first brood of the chinch-bug destroyed a larger 
ientage of these grains the larger was the surface covered by 
n,—we cannot possibly avoid the conclusion that wheat cul- 
* has a powerful effect on chinch-bug injury. If, further, we 
1 discover here the same contrast between Southern Illinois 
the other parts of the State as has appeared in previous dis¬ 
arms, we shall be confirmed in the opinion that a measure 
the reduction of wheat culture, which may promise the best 
its when early applied, may wholly lose its efficacy, and possi- 
even become a source of mischief, if postponed too long. 
Table IX. 
fral Illinois, 397 Towns. Injury to Small Grain, 1887, com¬ 
pared with Crop Areas for the Same Year. 
Degree of Injury. 
No. 
of Tps. 
Wheat. 
Barley. 
Rye. 
Oats*. 
Corn. 
Gra^s. 
371 
79 
28 
15 
1 
3 
1,559 
1,984 
2, 430 
. 2,321 
901 
2,068 
1 
3 
89 
52 
13 
41 
12 
47 
2,581 
2,467 
1,456 
1,828 
931 
2,251 
5,579 
5,135 
3,412 
3,551 
1,532 
5,461 
5,897 
5,902 
3,501 
5,486 
2,285 
4,275 
'ate. 
derable. 
1 
Great. 
aking up first the table for Central Illinois, we see at once a 
ded ascent from 1,559 acres of wheat per township where 
at and oats were uninjured, to 2,321 acres where these grains 
3 considerably damaged. That it is the increase in wheat that 
> be connected with this greater loss, and not the deciease in 
age of oats (from 2,581 to 1,828) is shown by combining the 
at and oats areas for each grade of injury, giving 4,140 for the 
term of the series and 4,149 for the last, the intermediate 
bers being one above and one below the average. Otherwise 
3d, wheat and oats have suffered more severely, in Central 
mis, as the wheat area increased while the joint areas of both 
ns remained unchanged, whence we can only conclude consist- 
y with the known preference of the chinch bug for wheat that 
the wheat increase which has caused the greater loss. We 
ce, further, that the acreage of grass shows neither marked 
3ase nor decline; while that of corn falls off some 35 per cent, — 
latter fact to be explained, as noticed elsewhere, by the rela- 
ly little attention given to corn in the broken regions es- 
ally adapted to wheat farming. 
