Friday, April 4, 2014

Did You Ever See A Hessian Fly?

Reader Kevin and I were discussing the very discouraging topic of what I call, "sorry wheat."  Sorry wheat is very disappointing if you really wanted it for grain.  It's been turned into a cover crop many times because the stand was just not there to take it to harvest.  Killing half dead winter wheat is one of the hardest things I've ever tried to do because it is normally such a survivor.

We shared pictures and I told him that I've never lost a crop planted in September so far.  Usually we try to plant after "fly free date" which is October 2 here.  Something about that timing, I've had 3 good crops now planted in September and only 50-50 planted in October.  Don't quote me on that, it's probably 80-20 but one spoiled crop is enough for me.

What is that blasted Hessian fly that caused this?  Has anyone ever seen one in the last century?

Most farmers wouldn't know a Hessian fly if it stung them.  Seriously.  They are that rare.  Let's keep them that rare.  I probably walk as much wheat as anyone in these parts and they are rare, thankfully, but I have seen them.  I think dad said they destroyed a crop or two in the 30's?

"The adult Hessian fly is a tiny, dark-colored insect about 1/8 inch long that resembles a large gnat or small mosquito. Females lay eggs on the seedling leaves, which hatch in three to seven days. Newly emerged maggots will move down to the crown of the plant and reside in the grooves of the leaf sheath and stem. They will feed on plant tissue by using their mouthparts like sandpaper and lap up juices that seep out.

Larvae are the only stage that damage wheat; adult flies do not feed. Maggots usually feed on the lower leaves and stems and reduce plant vigor. Infested plants become stunted and stiffly erect, and leaves are thickened with a bluish green color. A single maggot feeding on a plant for three days can stunt a young plant or tiller. Heavily damaged plants usually die during the winter.

Outbreaks of the Hessian fly have caused severe losses in wheat for the past 230 years in this country. It also may damage barley and rye, but not oats. Its damage was first observed in North America in the Long Island, NY area in the late 1770s.

It is not definitely known how the fly arrived from Europe or the time. My favorite story is the one that reports that the fly was found in the vicinity where Howe’s British troops were encamped. It was thought that Hessian soldiers in his army brought the pest from Europe in straw used for bedding; thus its name -- Hessian fly. The Hessian fly moved from Long Island approximately 20 miles annually until it reached the wheat growing region of the Great Plains. Problems associated with the pest and possible control methods are discussed at length in Thomas Jefferson’s agricultural writings.

Hessian flies caused a US shortage of wheat in 1836 that caused economic problems for farmers prior to the Panic of 1837.  It was reported in Ohio agricultural reports as early as 1847. In the latter part of the 1800s Hessian fly infestations were specifically reported in Crawford, Defiance, Seneca, and Wood counties of Ohio. Serious outbreaks occurred in Ohio in 1895 and 1920. Parts of Indiana had serious outbreaks as late as the early 1960s."

If you want good wheat, push the date.  If everyone listens to me, we will have another outbreak.  I don't think we plant enough soft red winter wheat for this to be a problem but it could be.  Do not drill wheat in wet soil when more rain is coming.  I've tried that and it resulted in sorry wheat.

Ed Winkle



  1. I never heard about this pest, an Asian native, although it apparently came to the U.S. via Europe. It is present and problematic in Northern Africa, where they have tried improving wheat resistance to it by crossing wheat with goatgrass, or the following experimentations (I don't know if it resulted into a commercial variety):

    "Distribution and proportions of Hessian fly resistance were evaluated in four populations of bread wheat lines advanced through 'Single Seed Descent' (SSD), 'Bulk', and doubled-haploid (DH) methods. These populations were all derived from crosses involving resistant parents and susceptible lines adapted to Moroccan conditions. The results of this study have shown a clear effect of the breeding method. The Bulk and SSD (F6) derived lines have shown a substantial residual heterozygocity while DH method has produced completely homozygous material. The observed proportions of resistance did not deviate from expected in the populations of lines derived through SSD and DH methods while evidence of natural selection for resistance was significant in the lines derived through the Bulk method."

    Apparently the Hessian fly can also be a pest for barley and rye. One member of this Cecidomyiidae family is a pest specialized in lavender, also from the larvae eating up the plant tissue. They hide right under the bark of the lavender bush, where they are protected from predators. Smart bugs!

  2. I was too quick, 4 soft wheat varieties with Hessian wheat resistance have been created in Morocco: Saada, Massira, Aguilal and Arrihane. The 2 latter are available commercially.

    5 hard wheat high yield varieties are also available: IRDEN, Marwane, Nassira, Amria and Chaoui.

    Poor barley is under attack from 2 different species of Hessian flies, M. destructor, M.
    mimeuri (ex. hordei). The third cereal seems to be oats, not rye (M. avenae).

  3. Good information, Chimel! My point is we have to respect the pest but since we don't grow wheat like we did here 50 years ago, we can change our practices a little.