Winter Wheat Diseases

Thursday, May 25, 2006

Craig Grau

Plant Pathology

Powdery mildew remains the most common disease observed in winter wheat fields.  Fungicides are an option for control, but predicting the need for fungicides remains problematic.  Powdery mildew is favored by cool and wet weather.  Rising air temperatures are predicted and should have a suppressive effect on powdery mildew.

There are defined restrictions on the use of fungicide treated winter wheat forage and grain for livestock feed.   Terminology on labels of most fungicide products tends to be incomplete on use of straw as feed if the crop was treated with a fungicide.   Straw has become a popular source of fiber in dairy rations.  For clarity, straw is defined as mature stems, leaves, husks, hulls harvested (baled or chopped) after grain is harvested. My conclusion, after reading labels and visiting with company representatives, is that straw, as defined in the previous sentence, can be feed to livestock if treated with Quadris, Quilt, Tilt, PropiMax, Stratego, Headline, Baytan 30 provided the interval between application and harvest restriction is met.  The days from application to harvest differs among the fungicide products registered for winter wheat.  The bottom line is carefully read the product label.