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They are more abundant in Louisiana, where wheatis never cultivated, 
than they are in northern Ohio, where this cereal is one-half of the 
grain crop. When they were working their greatest havoc in southern 
and central Illinois and southwest Indiana I looked in vain for them 
in northern Indiana. I do not understand why it is that a very large 
per cent of the adults found in Ohio, along Lake Erie, and in northern 
Indiana possess only aborted wings; yet lhavefound thisto be the case. 
As you all know, the insect parasites of this species are very few and 
of little account in holding it in check. For aid in this direction we 
must look to meteorological conditions unfavorable to their increase 
and the fungoid and bacterial parasites. These last will be found 
available during some seasons and within a certain limit, but nature is 
not likely to use one of her servants to annihilate another. We may be 
able to emphasize their work in this direction by continual artificial cul- 
tivation and distribution; further than this we can not expect to go, and 
the relief will at best be but local and temporary, though not by any 
means without value in limited areas. The only difficulty is in that we, 
with certainty, can not foretell a year of destructive abundance, and a 
few false alarms will so discourage the ordinary farmer that he will do 
nothing to protect himself. For my own part I feel quite sure that if 
the bugs can be induced to oviposit in spring in small plots of Millet or 
Hungarian grass they ean be controlled by the use of these vegetal 
diseases to far better purpose than to attempt to do so in the fields of 
ordinary cultivation. But there must be, somewhere, a central source 
of supply where requests for material can be promptly filled, as has been 
done by Prof. Snow, before the plan will prove a success. Next in value 
to such plats is, I think, the cornfields where the young bugs must of 
necessity congregate in compact masses and thus facilitate contagion. 
It would appear almost visionary to advocate spraying apple orchards 
in midwinter to protect the wheat crop, but nevertheless one of the 
most serious enemies of young fall wheat passes its egg stage on the 
twigs of the Apple during the winter season. I refer to the Apple Leaf- 
louse, Aphis mali Fab. Soon after the young wheat plants appear in 
the fall the winged viviparous femalesof this species flock to the fields 
and on these give birth to their young, which at once make their way 
to the roots, where they continue reproduction, sapping the life from the 
young plants. On very fertile soils this extraction of the sap from the 
roots has no very serious effect, but where the soil is notrich, and espe- 
cially if the weather is dry, this constant drain of vitality soon begins 
to tell on the plants. Though they are seldom killed outright, these 
infested plants cease to grow, and later take on a sickly look, and not 
until the Aphis abandons them in autumn to return to the Apple, 
do they show any amount of vigor. It is very seldom that the affected 
plants fully recover, at least in autumn, and the result must be to 
reduce their productiveness the following year. 
The greater number of serious pests of our fields of Indian corn are 
