This is Nathan Mueller, UNL Extension Educator for Cropping Systems, in Fremont, NE. Each Monday, I conduct a Dodge County Crop Condition Tour that I write up on my blog at croptechcafe.com posted with plenty of pictures. Agronomic issues growers may be seeing this week include potato leaf hopper in alfalfa and corn leaf diseases.
I have noticed some significant potato leaf hopper injury to alfalfa stands. Potato leafhoppers have the potential to cause economic injury every year in Nebraska usually to second and third cuttings. The 1/8 inch long, bright green, wedge-shaped insect cause’s injury by injecting a toxin into the plant as they feed. Treatment decisions are based on the numbers captured by a sweep net and you do not need very many to cause a problem. Early second cutting can be the best management option. For more information on potato leafhopper treatments and pictures of what damage looks like, visit my blog at croptechcafe.com.
On Monday, we had low incidence and severity of most corn leaf diseases, even on irrigated corn after corn. Diseases observed at low incidence and low severity were gray leaf spot, common rust, northern corn leaf blight, all fungal diseases. Goss’s Bacterial Wilt was at low incidence, but moderate severity in some hybrids. Susceptibility of corn to these diseases is dependent on the hybrid. In particular, please contact your corn seed representative to discuss which hybrids are more susceptible to gray leaf spot and northern corn leaf blight and prioritize scouting of these hybrids. Seed company data has shown that an economic return is less likely for fungicide applications on hybrids more resistant to gray leaf spot, especially now at low commodity prices. Visit by blog at croptechcafe.com to see pictures of these diseases.
Lastly, please mark down on your calendars for the Soybean Management Field Day in Snyder, NE on August 15. To view the program, visit cropwatch.unl.edu. As always, please feel free to contact me, Nathan Mueller, at 402-727-2775.