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The common native Two-striped Locust is very numerous throughut the infested 
region, doing considerable damage. 
Remedies. — Besides the usual methods of killing locusts, some of which are very- 
valuable if carried out at the proper time, there is but one other excellent remedy- 
left to prevent further injury: plowing the ground after eggs have been laid. 
This remedy has been applied two years ago on a large scale in Otter Tail County 
and has proved a complete success. As the conditions in the newly infested regions 
are similar, there is no doubt that similar results will be obtained if the same remedy 
is carried out thoroughly. All the locusts now infesting the invaded counties came 
from fields that were not plowed. In places where the whole of the cultivated soil 
was plowed, no locusts could be found. Of course at the time of writing this bulle- 
tin the state of affairs is different, as the insects have scattered over a much larger 
area. But if every farmer will plow all his stubble land either this fall, after the 
eggs have been laid, or in early spring, no fears of losses by locusts need be enter- 
tained. But to make the reader understand the case more clearly, it is necessary to 
describe in detail how the eggs are laid and what effect plowing will have. I quote 
from Bulletin 8, published by the Station during July, 1889. 
To repeat again : " If we desire to get rid of the migratory species of locusts now in- 
festing several counties of the State, it is absolutely necessary to plow every inch of 
the cultivated ground throughout the invaded region. Of course prairies are excepted, 
the soil in them being filled with a dense mass of roots, thus being unsuitable for the 
purpose of egg-laying. Simply cultivating in spring, as advised by some, is perfectly 
useless and proved a total failure Avhere tried. Summer fallow invites the locusts 
to deposit their eggs in soil thus prepared, and all land thus treated must be plowed 
again, either later in autumn or early in spring." 
Natural remedies. — There are at this time many natural agencies in our favor and 
working for us, and no doubt immense numbers of locusts will be killed by them. 
Nearly if not quite all the parasites known to infest locusts are found in large num- 
bers throughout the invaded region. In some places the Eed Mite was found in im- 
mense numbers infesting not alone the bulky Two-striped Locust, but also those mi- 
gratory species which love drier soil. In some fields in which the locusts had hatched 
nearly every individual had from five to twenty of these mites fastened to its under 
wings and the locusts were doomed. Evidently they knew this as well, as they did 
not move about in such a lively manner, but seemed out of sorts. But these were 
exceptional cases, as all the adjoining fields of wheat were overrun Avith healthy 
specimens — too healthy to suit the farmer. The explanation lies in the fact that the 
healthy locusts had escaped all danger from the Red Mites by migrating to the land 
of plenty, the wheat fields. Numerous other parasites occurred almost everywhere, 
but chief among them was one of the "old-fashioned" Potato Beetles, or Blister Beetles. 
This insect (Epicauta pennsylvanica) was so numerous as to seriously injure the po- 
tato crop. And yet, though very injurious to potatoes, this beetle ought to be pro- 
tected for once, as in its earlier stage it feeds exclusively upon the eggs of the locust. 
Many predaceous insects are also in full operation to reduce to some slight extent 
the numbers of the intruders. It was a crnel yet withal a pleasant sight to see the 
large numbers of Ground-beetles (Calosoma calidum) giving battle to the locusts. 
Even large specimens were attacked, and notwithstanding a most desperate struggle 
the locust was soon consumed. Another beetle (Pasimaclius sp.), much more shy 
in all its actions, being a nocturnal insect, was found in large numbers engaged in 
devouring the enemy. Even spiders assist in this good work, and a number of the 
common Wolf Spiders (Phydijppus trigunctatus) were seen to attack and kill locusts. 
