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moist weather, and which burst the pores, producing an exudation that 
formed on the surface of the stem. The more probable theory is that it 
is a parasitical fungus that forms on the straw in wet, muggy weather, 
operating upon the grain by some poisonous quality, or by obstructing 
the circulation. 
A remedy for rust will doubtless continue an impossibility till human 
control shall be acquired over the incidents of natural change, oyer fluc¬ 
tuations in the earth and air—over storms and seasons. It can only be 
guarded against by the cultivation of hardy varieties of grain, by the 
careful drainage of wet portions of the field, and by early harvests. 
Those grains of which the stem is hard, stiff and brittle, are less liable 
to rust than others. Those of which the halm is soft, thick and spongy 
are hardly safe under the most favorable circumstances. 
Blight, mildew and rot are kindred accidents that affect the heads of 
wheat. They are probably caused by wet, or by some unknown influence 
which prevents the maturity of the grain, perhaps changing the sap by 
stagnation and fermentation into a decomposing agent. It is seldom that a 
crop is injured to any great extent by these causes—when injury is exten¬ 
sive it is temporary and probably unavoidable. They are the accidents 
which befall this, as other accidents befall other pursuits of industry, 
against which foresight is vain and prudence cannot provide. 
A number of insects have for the last fifty years, been the worst ene¬ 
mies of the wheat crop. The principal of these is the Hessian Fly, the 
ravages of which have been so general and so fatal as to render a more 
particular account interesting. 
This insect is known in science under the name of Cecidomxjia Destruc¬ 
tor. Its vulgar appellation arose from the traditional belief that it was 
brought to this country in some straw by the Hessian troops, under Sir 
William Howe, in the Revolution. Ho accounts are given of its exist¬ 
ence in America before that time. It was first observed in the neigh¬ 
borhood of an encampment occupied by the Hessian mercenaries on 
Long Island. Having multiplied there, they spread over Southern and 
Eastern Hew York and Connecticut, proceeding inland at the rate of 
fifteen or twenty miles a year. They appeared about Saratoga in 1789, 
and west of the Alleghanies in 1797. They appeared in Osage county. 
