Weed Management Means Thinking Long-Term
With the 2009 season underway, growers are hoping that despite tough weather conditions, this season will be successful. One key to healthy fields and strong yields is proper weed management.
The terms weed control and weed management are two strategies that represent quite different approaches to how weeds affect crops. Weed control is only looking at the short term, killing weeds as they occur to deal with immediate repercussions; while weed management is a long-term, proactive approach that can help increase yields and profit potential for that field in future years.
With tough-to-manage weeds, like waterhemp, the increasing prevalence of glyphosate-resistant populations continues to grow, especially in states like Missouri and Illinois. Using "tried-and-true methods" may not be as successful moving forward, varying weed management practices to alleviate pressure of resistant populations that to continue to develop.
Long-term reliance on glyphosate-only programs have often been used, and can lead to glyphosate-resistant weeds. Alternating modes of action and rotating crops, as well as the use of pre-emergence residual herbicides can help keep fields clean. A recent Penn State University Field Crop News article encourages the use of soil-residual herbicides to get longer control throughout the season and help with weeds that have a longer emergence pattern, and alleviate pressure on herbicide resistance that is generally applied post (ALS, glyphosate).
A multi-year weed management program looks forward at how to successfully manage a field, using multiple modes of action that target the toughest weeds, but also not allowing other species to establish dominance and create future problems. Using states like Missouri and Illinois as an example for other states throughout the Midwest, implementing proactive strategies to reduce selection pressure makes the most sense.
With the onset of glyphosate-resistant weeds in the Midwest, how has your attitude toward weed management changed? Specifically, what practices have changed? What do you think are the benefits or problems with your strategy?