Arkansas Palmer Amaranth Found Resistant to Field Rates of Glufosinate

by Tom Barber, Jason Norsworthy and Tommy Butts 

Weed resistance to Glufosinate (liberty):   What options do we have left if glufosinate (liberty) is no longer an option for weed control in soybeans? I have personally found palmer amaranth in both Clinton and Washington counties. Here are a few key factors to consider in order to utilize liberty in the correct manner

 1.       Use labeled rates 32-44 oz.

2.       Spray Tips matter. Using the correct spray tips plays a major role in weed coverage/control

3.       Gallons per acre is a big deal. Make sure to be spraying the correct amount of water depending on the rate of liberty being used

4.       Layer residuals. The goal on my farm is to never have to use liberty, enlist, or dicamba. I am able to accomplish this by properly layering residuals in a timely manner

5.       Apply to weeds at or less than 4 inches tall. Do not wait until you see the weeds “stick out over the beans,” at this point you are too late and are at risk for building resistance. Actively scout your fields twice a week, or call a top ag sales agronomist to take a look. We are happy to help and do not charge for scouting.

6.       Consider applying foliar products like Take off LS and Ascend with your post pass of herbicide. These products are proven to not only improve yield they also create faster canopy closure thus giving weeds less time to have the potential to germinate.

To read the article and learn more, visit: https://arkansascrops.uaex.edu/posts/weeds/palmer-amaranth.asp