As the time approaches for planting small grains, now is the time to start thinking about Hessian fly . In the 1800s and early 1900s, this insect was a devastating pest of small grains in this country as its scientific name, Mayetiola destructor, implies. Hessian fly larvae feed between the leaf sheath and stem, causing stunting, reduced tillering, stem breakage, and yield loss. The Hessian fly larva spends the summer in a puparium, a hardened shell that protects the last stage larvae. In late summer, the larva pupates inside the puparium, and emerges as an adult fly.
Adults mate and lay eggs on volunteer or early-planted grain.
These eggs hatch, larvae develop, and then overwinter. Fortunately, adults only live a few days. That is why you have an opportunity to avoid colonization by the Hessian fly by planting after a certain date in the fall. The fly-free date differs by location across the state, with later dates the further south you go. For example, for Cheboygan, Oscoda, and Osceola counties, the fly-free date is already past, i.e. it is safe to plant small grains in these areas.