Proper weed identification is the first step. Tim Dahl with Syngenta says some weeds can be tough to tell apart, especially in corn and soybean fields.
"Later on in the season, as the plants get older, they're pretty easy to tell apart. The way that I tell them apart is I take the leaf and the petiole, and the petiole is just the branch or the structure that attaches to the stem and the leaf. You fold that leaf over and if the petiole is longer than the leaf, you're probably talking about Palmer amaranth. The petioles are that structure that attach the leaf to the stem of the plant. With waterhemp, it would usually be much shorter than the leaf."
and he says growers should be concerned if they've misidentified weeds and have been treating for the wrong type.
"We have to control all the weeds in the field. So, obviously, if we're talking about a giant ragweed versus waterhemp, yes. We absolutely need to make sure we get those identified correctly. A giant ragweed will germinate much earlier in the season and come from a much deeper depth. So, obviously it's a little bit different management strategy. But, we still need to control them, control them all. Obviously, different herbicides are better at controlling different weeds so, yes. We have to make sure that we identify the weeds correctly so that we can control them when and with the best product."
For more information on weed identification, coaching on resistance management and localized solutions, growers can go to www.ResistanceFighter.com.