The significance of Ohio’s extremely wet spring is well documented in terms of corn and soybean production, but wheat fields also suffered considerably from the abundant precipitation.
“This has not been the best season for wheat,” said Pierce Paul, Ohio State Extension specialist and plant pathologist.
Farmers faced everything from flooded wheat fields, to disease issues and prevented spring nitrogen applications due to the severity of conditions, he said. Because of such conditions, yield estimates across the state range from as low as 25 bushels per acre to as high as 90.
Paul attributed the lower-yielding fields to a combination of flooding, missed nitrogen applications and disease pressure.
“The rains created moist, humid conditions,” he said. “Any time we have moist, humid conditions, we’ll have diseases.”
The most common diseases in Ohio fields this year included powdery mildew, Septoria, Stagonospora and a fairly significant appearance of head scab. But, Paul said, while the incidence of head scab is relatively high, it isn’t as bad as last year, based on his field surveys 145 fields.
Paul estimated average scab incidence anywhere from 8 to 10% across the state, with less affected fields as low as one percent of heads impacted, and more severe cases ranging as high as 45 of 100 heads showing symptoms of scab. He said it is difficult to generalize for the state as a whole due to the wide range from least to most affected.
The National Ag Statistics Service at the U.S. Department of Agriculture estimated 10% of wheat ripe as of Monday’s crop progress report, which is well behind the five-year average of 24%. Even so, Paul said farmers are already cutting wheat in southern Ohio.
Of concern to those producers harvesting cereals from fields affected with head scab is vomitoxin. Paul said some elevators typically reject wheat delivered with vomitoxin levels above eight parts per million, and will discount prices for levels of 2-8 ppm.
To minimize vomitoxin issues, farmers should follow two key recommendations during harvest.
“Turn up the fan speed on the combine,” Paul advised. This will blow some of the affected kernels out of the combine and lower the overall level of vomitoxin in the bin.
Secondly, harvest as quickly as possible when conditions allow. The longer wheat stands in the field after it is ready to cut, the greater the opportunity for additional accumulation of toxin and reduction in overall grain quality.
Paul said farmers should learn two key lessons from growing wheat in such wet conditions: plant disease resistant varieties, and plan timely applications of fungicides.
“A lot of farmers went out and applied fungicides, and we saw a clear difference,” he said. “Also, resistant varieties clearly performed better than susceptible varieties.”
Noting data from fungicide applications on 145 fields surveyed, Paul said correctly timed applications provided good suppression of head scab as well as foliar disease control this season.
Along with correctly applying fungicide, he said investing in resistant varieties would allow farmers to minimize disease pressure and maximize yield potential next year.