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Corn Weeds

All Corn Weeds Content

aerial view of South Dakota farm and surrounding land


During the growing season, SDSU Extension provides weekly production recommendations.

corn field with sunrise in the background


Nearly one out of every three dollars generated by South Dakota agriculture starts in a corn field. Two of every three rows of corn become ethanol.

abandoned barn surrounded by flood waters. Photo by Jeannie Mooney, FEMA

Effects of Spring Flooding on Weed Seed Movement

How does spring flooding impact weed seed movement and dispersal? The flooding that is occurring from spring snow melt may cause weed seeds that are on the soil surface or eroded soil to move, and possibly long distances.

a variety of cover crops growing in a field

Herbicide Considerations for Cover Crop Planting in 2019

Long residual pre-emergent or early post-emergent herbicides may cause stand reduction or complete failure of cover crops. Depending on efficacy of the herbicide, each situation can both affect in-season and/or post-harvest cover crop establishment.

Soybean plants with wilting, cupped leaves as the result of dicamba herbicide damage.

South Dakota Herbicide Damage

As the spray season starts, it is always good to be aware of resources and testing facilities where you can send in possible herbicide-affected plant samples. SDSU Extension offers suggestions on how to handle possible herbicide damage situations as well as recommended labs that receive plant matter samples to test for herbicide residues.

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.

Kochia plants growing in a test plot field.

Timely Control of Kochia

Warm temperatures across South Dakota could allow Kochia to get a head start this spring. Kochia control, like all weed control, takes proactive farm management to prevent weed establishment from occurring, rather than reacting to the latest problem.

Field pea cover crop blend growing in a field of corn residue.

Herbicide Residual Effects on Cover Crops After Corn Silage

As cover crop usage has increased in recent years, managing weeds through a longer residual herbicide program has become more complicated. Learn some considerations for cover crops following corn silage.

Several ears of sweet corn on a table.

Weed Control in Sweet Corn

When growing sweet corn on a large scale, weed control can be challenging, and certain steps need to be taken before choosing an herbicide.

A farmer watching the sun rise in a bare, unplanted field.

Crop Tolerance to Soil Herbicide Residual

Some herbicides can persist in soil, especially dry soil. Herbicide carryover could be an issue in 2021 across the state depending upon last year’s moisture levels and field conditions.