Issue No. 17/July 18, 2008
Japanese Beetles Are Causing Serious Concern in Some Areas
Signs of substantial defoliation in soybeans and the presence of lots of Japanese beetles likely warrant an insecticide application, but using insecticide to prevent an infestation is not appropriate.
Western Corn Rootworm Adults Are Active, Too
Though the numbers of western corn rootworm adults this season are moderate, the species is a constant threat.
With a Few Exceptions, Corn and Soybean Insects Are Relatively Quiet Thus Far
Insects are not posing many problems in corn or soybeans, but reports from throughout the Midwest suggest the need to watch for western bean cutworms, soybean aphids, and armyworms feeding on corn leaves.
Fungicides for Soybean: What Important Foliar Diseases Need to Be Controlled?
Septoria brown spot and frogeye leaf spot are common in Illinois and can be controlled with foliar fungicides. Downy mildew and bacterial blight are also common, but cannot be controlled with foliar fungicides.
Plant-Nutrient Value of Wheat Straw
What would be the effects of baling this year's wheat straw? Steps are outlined for calculating the nutrient value that would be removed.
Reports are provided this issue for northern and west-central Illinois.