Extension expert releases weekly IPM report
Weather -- Soil temperatures at the MAWN site south of Dundee reached 50.2 degrees on Saturday, April 18 but have dropped 12 degrees since.Scattered to moderate rains the past couple of days, and much cooler than normal temperatures have kept soil conditions too wet for most field work.
Alfalfa -- Overwintering stands appear thin but adequate in many fields.Iowa State is reporting Alfalfa weevil activity and feeding.When soil temperatures exceed 48F adult weevils will begin laying eggs.One female adult moth can insert 5 too 20 eggs at a time into alfalfa stems.
Corn -- Purdue, Ohio State and the University of Illinois are reporting black cutworm moths blowing up from the southern states on recent storms.Moth arrival, along with the use of heat units to predict the beginning of larval activity, allows Entomologists to be able to predict with some degree of accuracy when and where crop damage is most likely to occur.Black cutworm moths are attracted to weedy fields such as chickweed, Shepherd's purse, peppergrass and yellow rocket.Not all Bt hybrids offer adequate protection against black cutworm damage.Refer to Dr. Chris DiFonzo's handy Bt trait table at www.msuent.com.
Soybeans -- Soybean seed will sit in the ground at soil temperatures in the 40's.Seed rot and other seedling diseases are more of a concern than seedling insects.Seed treatments for diseases and Soybean cyst nematodes should be a first consideration, partly to save on cost with the prospect of lower soybean prices.Iowa State is reporting a high mortality rate of overwintering adult bean leaf beetles.A report from the University of Wisconsin suggests planting soybeans by maturity date.Although this seems intuitive, farmers here may plant earlier maturing soybeans for a variety of reasons, including harvesting early to allow for timely wheat planting.
Wheat -- Purdue and Ohio State are also tracking and trapping Armyworms which also blow up north and usually are attracted to winter wheat fields.I will be trapping in a wheat field for Martin Nagelkirk of MSU Extension.I need a farmer willing to allow me to put a trap up in their wheat field.