Skip to main content

Soybean Weeds

All Soybean Weeds Content

aerial view of South Dakota farm and surrounding land

Pest & Crop Newsletter

SDSU Extension publishes the South Dakota Pest & Crop Newsletter to provide growers, producers, crop consultants, and others involved in crop production with timely news pertinent to management of pests, diseases, and weeds in South Dakota.

Harvested corn field with field pennycress throughout.

Soybean Cyst Nematode Management Plans Should Include Proactive Weed Management

While soybean cyst nematode can be managed through use of resistant varieties and crop rotation, presence of alternative weed hosts can negate the benefits of these practices by providing a host for soybean cyst nematode to continue to accumulate in the soil.

Waterhemp growing at he edge of a soybean field nearing harvest.

Checking Weed Control at Harvest

With harvest now in full swing, don’t forget to look at your fall weed control. What are the weeds that are left in your crop? Do you know what weeds they are? Is there a weed that you do not know?

Canada thistle growing in a pasture.

Fall Noxious Weed Control

Fall weed control can give the best weed control, but it also can be a poor time. If the noxious weeds were sprayed or clipped earlier this summer, and there is good weed growth now, this would be an excellent time to spray these weeds and get a good kill.

a man standing in front of a cornfield

SDSU Extension Weed Evaluation Extension Demonstration Available at South Dakota State Fair

September 01, 2020

The SDSU Extension Weed Evaluation Extension Demonstration project will be available to the public at the South Dakota State Fair September 2-September 7.

A red, tractor-mounted sprayer with its tank being flushed by a hose connected to a large truck.

Alternatives to Postemergence Dicamba Applications

Cancellations of three dicamba labels on June 6, 2020 by the U.S. Environmental Protection Agency, left many farmers looking for options for effective weed control this summer.

Sunny field with large puffy clouds and blue sky

2020 South Dakota Pest Management Guides Released

August 25, 2020

The 2020 South Dakota Pest Management Guides are now available for free on the SDSU Extension website.

Left: Marestail growing in a field. Right: Young marestail plants emerging from soil. A dime is placed near the plant to demonstrate its scale.

Marestail Fall Control

No-till crop production in South Dakota is on the rise. Marestail is a native plant to the United States and is considered either a winter annual or biennial species that is often difficult to identify at the rosette stage. In the Dakota’s, the Marestail population will germinate in the fall and bolt in the spring.

Kochia growth spreading amongst a patch of soil.

The Fall Advantage of Kochia Control

Kochia is a problem in row crops in North Central South Dakota. New Post-emergent options in corn and soybean have helped alleviate Kochia competition from many fields, but these herbicide options shouldn’t be completely relied upon for a long-term plan for control.

A sprayer applying pre-emergent pesticide to a bare field.

Herbicide Rotation Restrictions

This is a quick reference guide to common herbicides and their rotation restrictions for selected crops.