Marketing disease infected wheat

Farm Forum

As wheat harvest got underway, early reports from south-central South Dakota indicated yields ranging from 35 to over 100 bushels per acre, with test weights and quality. More recently, disease problems have been showing up.

Some of the scab (Fusarium Head Blight) infested wheat reported earlier has made its way to the marketplace, with the worst report to date being 7 ppm of DON (Deoxynivalenol, also referred to as vomitoxin), with a test weight of 49 lbs/bushel. With the limit for DON in human food products set at 1 ppm by the FDA (Food and Drug Administration), and the lowest acceptable test weight for wheat being 50 lbs/bushel, this crop is not marketable for human consumption. The food industry is known to set standards that are more restrictive.

Each grain elevator may set their own level of DON that they will accept, with plans to mix the grain with that containing no DON or a level below the industry standard. Individual producers could also take steps to improve the marketability of their crop such as having it cleaned, and/or mixing with other wheat containing low levels or no DON. In addition to standard cleaning equipment, a gravity table could improve the finished product as scab affected kernels are lighter than healthy ones. Any mixing done by producers should be approached with caution as good wheat could be made unmarketable. Representative samples of both lots of wheat should be tested for DON to ensure that the final product will be within the accepted level or that which would be docked at a minimum rate.

As mentioned in an earlier column, DON levels in straw can accumulate at much higher levels than found in the grain. Harvesting straw from scab infected fields for livestock forage should be pursued with caution.

Ergot is also showing up in wheat. The most common sign of ergot infection is the dark purple to black sclerotia (ergot bodies) found replacing the grain in the heads of cereal crops and grasses. The sclerotia replace the developing seeds and can stick out past the glumes. The sclerotia can also be easily seen in grain samples and the USDA Federal Grain Inspection Service grain standard, used by elevators, grades grain as undesirable when the level of ergot exceeds 0.05% by weight. The ergot bodies may be the same size as the grain seed (typically seen in wheat) or may be several times the size of the grain seed as sometimes seen in rye.

As with scab, ergotty wheat can be improved by cleaning, possibly with a gravity table, and/or by mixing with ergot free grain. Once again, individual producers should approach mixing their own wheat with caution to avoid contaminating clean grain.

Pesticide Container Recycling and Waste Pesticides

The South Dakota Pesticide Container Recycling Collection program started the season on July 14 and is working through the schedule of over 40 stops. Plan to take your empty pesticide containers to a collection held in your area. Visit for more information and a schedule of the container recycling program and information on the Waste Pesticide Collection Program.