4 Difficult Weeds to Watch in Soybeans

Something went wrong. Please try again later...

Among the most difficult weeds for many Midwest farmers are marestail, waterhemp and giant ragweed. And a worrisome weed encroaching into more soybean fields is Palmer amaranth, a hard pigweed to control.

Fast-growing and prolific, marestail can be resistant to glyphosate (Group 9) and ALS inhibitors (Group 2) so prompt control is important. 

During its growing season, waterhemp can grow 1.5 inches per day. This stubborn weed also shows resistance to many herbicides, including glyphosate. 

Giant ragweed
Glyphosate alone may not control it. Farmers from Iowa east into Ohio may also see giant ragweed that is resistant to Group 2 herbicides. 

Palmer amaranth
A weed that’s been giving Southern farmers fits, Palmer amaranth now is moving north. It may resist glyphosate, triazines, PPO inhibitors or HPPD inhibitors. It grows fast and can produce more than 500,000 seeds per plant.

A cold, wet spring can make preplant and preemergence herbicide applications a challenge to schedule. Soybean farmers need to control difficult weeds in a timely manner to preserve yield potential.

Using multiple modes of action in a timely manner is key for effective control of these weeds. Sonic® herbicide is a valuable tool offering two nonglyphosate modes of action to provide long-lasting residual control. Taking advantage of this preemergence herbicide to control weeds early can help farmers time postemergence applications more accurately, obtain better full-season control and protect more yield potential.

Sonic® is not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Always read and follow label directions.


Inputs & Insights

Receive the latest retailer tips and product information in your inbox.

Browse Inputs and Insights

Subscribe to Inputs & Insights

Weed Management Resources
Overcome weed challenges with our solutions.

See Soybean Herbicides