Herbicide resistant weeds, especially marestail and pigweed, are becoming a widespread problem even in the county; however, research is finding adding cover crops to your rotation is a good way to control these weeds.

Marestail can germinate during the growing season, overwinter and can have subsequent germination flushes through the following spring and summer, so identifying potential problems now is the key to control it for next year.

If you notice rosettes in the fall, an application of tank-mixed glyphosate and 2, 4-D can effectively control small plants before seeding a cover. Cereal rye seeded at 60 pounds to the acre will help suppress winter annual and other late winter/ spring annual weed germination, while improving soil structure and helping to breakdown crop residue.

In the spring, the rye should be terminated with a burndown with 2 modes of action during the boot stage.

This will provide adequate control of the rye and catch any weeds that might have germinated after seeding. After termination, plant an early maturing bean early in the season to provide a good window for cover crop seeding that fall.

Over the summer you should continue to scout for weed pressure in your fields and identify and treat problems as necessary.

Once the beans are harvested in the fall, seeding a cover that has a lower C: N ratio will help release captured nitrogen when the following corn crop needs it, about six to eight weeks after planting.

Good mixes to plant include oats and radishes, ryegrass and clover or peas or wheat/rye and clover.

In the spring, terminating the cover and planting corn into this residue followed up with a post emergence spray as needed will help significantly reduce weed impacts in fields.

By keeping the soil covered with a living plant for as much of the growing season as possible and addressing weed issues early you cannot only improve soil health, crop production and water infiltration, but you can significantly reduce commercial inputs improving the bottom line.

Keep in mind it’s never too late to seed a cover crop. Right now the soil temperature is still favorable.

Andy Gaver is a conservationist with the USDA Natural Resources Conservation Service in Butler County.