Weekly Ag Update

By ned birkey

msu EXTENSION EDUCATOR EMERITUS

SPARTAN AG 

 The National Weather Service Climate Prediction Center’s outlook to Sept. 22 calls for temperatures leaning below or near normal but leaning above normal outlook for precipitation. The MSU Enviroweather station at Applewood Orchards, Deerfield, Mich., has recorded 2,688.6 growing degree day (GDD) (heat units, base 50ºF) since April 1, 2026, compared to 2,536.5 GDD a year ago and a five-year average of 2,580.9 GDD. Precipitation since April 1, 2026, has been 21.05 inches, compared to 15.65 inches a year ago and a five-year average of 15.94 inches. Since Aug. 1, precipitation has been 5.94 inches, compared to 1.89 inches a year ago and a five-year average of 3.94 inches.

Fall armyworm is an occasional pest whose moths blow into Michigan, Ohio and the Midwest via storm fronts. The moths then lay eggs which hatch into caterpillars that are the damaging stage of this pest that feeds on corn, small grains and forage crops. This pest does not overwinter as opposed to true armyworm. Although an occasional pest, monitoring by Ohio State, Michigan State does not substitute for farmer scouting as the early instar caterpillars are small and easy to miss and larger caterpillars can cause damage to crops and are not very susceptible to insecticides. In alfalfa, a sweep net is useful for scouting while in corn examine leaves, tassels or ears, with a raggedy feeding pattern. For more information on field crop insecticides, download the Michigan/Ohio Field Crops Inset Pest Management Guide.

Cover crop use is expanding throughout the U.S., particularly as more farmers no longer raise livestock when the use of pastures and hay provided crop rotation patterns. Now, one of the first questions to answer before deciding upon a cover crop choice is how to terminate it next year, perhaps by winter kill, spring tillage or herbicides. With legumes, grasses and brassica choices, cover crops can provide a winter cover from erosion, act as a nutrient sink, provide soil structure benefits or non-chemical weed control. Incentive payments from USDA NRCS can help get farmers interested, and farmers learning from other farmers provides a local situation that shows that covers work.  Allowing cover crop users to do grazing will also benefit livestock farmers.

Harvesting produce can be tricky as not all crops ripen in the same way. Pears are picked before they soften, melons and cucumbers must be fully mature before cutting and tomatoes can finish ripening indoors if needed. Potatoes can be harvested after the above ground foliage has died back, then wait one to two weeks to let the skins thicken. Pumpkins will not continue to ripen off the vine so wait until their skin is so hard that it can’t be pierced with a fingernail, then stored in a cool, dry place until you are ready to display them. Watermelons may be the hardest to know when to harvest because they remain firmly attached to the vine even when they’re ripe. Signs of ripeness include dull green color, very hard skin, underbelly turns buttery yellow, and perhaps a dull thumping sound that it makes when it’s ripe.