Hessian fly
A Hessian fly is a well known insect pest. It is a small fly. It is allied to the gnat and the midge. The adult female is about one-tenth of an inch in length. The body is brown with blackish upper parts. It has dusky gray wings, surrounded with fringe. Two generations are raised in a year. In September the fly lays its eggs in growing winter wheat. The maggots hatch in from four to fourteen days. The fall generation lives over winter in the wheat field and is ready for work in the spring. It matures and lays eggs again in May, this time in the joints between the leaf sheaths and the stem. The May generation is the one that does the damage. The maggots turn into pupae, known from their appearance as flax seed, and work their way into the joints of the wheat stem. The stalk loses strength and the head falls over worthless. Of the various cereals, barley and rye are least subject to attacks of this insect. The wheat raiser dreads the Hessian fly more than he does the chinch bug. Directly and indirectly, it is said to cause the American farmer an annual loss of millions of dollars. In damp seasons certain parasites attach themselves to the Hessian flies and all but exterminate them. For a year or two the farmer's fields are comparatively free from the pest.
