The control of flies in rural and suburban districts offers a much more
difficult problem. Here it is often out of the question to remove all
manure from the premises twice a week, and the problem is to find some
method of disposal or storage which will conserve the fertilizing value
of the manure and at the same time prevent all flies from breeding, or
destroy such as do breed there.
With this idea in mind, it has been recommended that stable manure be
collected every morning and hauled out at once and spread rather thinly
on the fields. This procedure is advisable from the point of view of
getting the maximum fertilizing value from the manure. Immediate
spreading on the fields is said largely to prevent the loss of plant
food which occurs when manure is allowed to stand in heaps for a long
time. This method will be effective in preventing the breeding of flies
only if the manure is hauled out promptly every morning and spread
thinly so that it will dry, since it is unfavorable for fly development
in desiccated condition. The proper scattering of the manure on the
fields is best and most easily and quickly accomplished by the use of a
manure spreader, and many dairies, and even farms, are practicing the
daily distribution of manure in this way. Removal every three or four
days will not be sufficient. Observations have shown that if manure
becomes flyblown and the maggots attain a fairly good size before the
manure is scattered on the fields, they can continue their development
and will pupate in the ground.