Keeping Weeds Under Control

This is a picture I took when I was out spraying pre-emergence herbicide on my soybeans. For a number of years we relied completely on Round-Up to control weeds. We would plant the beans, let the weeds grow and spray them with Round-Up. Round-Up is a contact herbicide, so it does not have any residual soil activity. Another flush of weeds would grow and we would spray them again with Round-Up. The end result was perfectly weed-free beans to harvest in the fall.

Mother Nature seems to always find a way to adapt if you do the same thing year after year. The past couple of years we started to see some troublesome weeds like giant ragweed and waterhemp seeming to have adapted to the Round-Up ready system. Many years ago, weed scientists did warn us about the possibility of this happening. So we adapted, too. Instead of letting all the weeds grow, we went back to a pre-emergence application and a post-emergence application of Round-Up and a couple of other herbicides. The key was to change it up and use multiple herbicides with different modes of action. As one weed scientist said, we need to become more "unpredictable" with our weed control program.