No. 5 Article 2/May 6, 2011

Weed Management Reminders for a Wet Spring

Much of the vegetation visible from the road is winter annual species, including the now obvious yellow-flowered cressleaf groundsel (butterweed) and yellow rocket. Certain summer annual species, such as common lambsquarters and smartweeds, also have begun to emerge. When field conditions become conducive for planting, several possible scenarios exist for managing existing weed vegetation. One is that planting will be done before any type of weed management program (tillage or herbicide application) is implemented to control existing vegetation. In other instances, herbicides applied earlier this spring often have done well at controlling winter annual species. The following reminders and suggestions might help farmers overcome some of the weed management problems already visited upon them by this season's challenging planting conditions.

Fields where a herbicide was applied several weeks ago are excellent candidates for scouting before planting. The heavy precipitation in many areas of the state may have moved some soil-applied herbicides deeper into the soil profile than is conducive for good weed control. If weeds are present, you should consider controlling them before you plant. Why not just wait to spray after planting? That may be feasible, but the planting operation will likely injure some of the weeds, and they will need time to recover before being sprayed. To waiting is also gambling that the weather will cooperate and allow you to make the application before the existing weeds begin to adversely impact the crop. The less-than-ideal growing conditions may also increase the likelihood of corn injury from some soil-applied herbicides.--Aaron Hager

Close this window