What is in this article?:
- Growers share resistant pigweed control strategies
- Turned off dry
- First noticed along waterways
• It’s important to overlap pre-emergence treatments and chemistries by following a calendar rather than by driving out into the field to see if pigweeds are emerging.
• When you come out to plant, you’ll think you have a clean field. But you won’t — the pigweeds are there.
Growers shouldn’t be scared of resistant pigweed, they should just go after it.
First noticed along waterways
John Newby, who farms in Alabama and Tennessee, says he first starting seeing pigweed up and down the river and along the creeks on his farms. “We first thought we didn’t have them. We thought maybe we didn’t get glyphosate on them because of the rain. But about four years ago, we decided we had them,” he says.
Pre-emergence herbicides have worked well, says Newby, and the yellow herbicides have been very effective.
“We’ve started putting out more liquid nitrogen, putting out the yellow herbicides, and then incorporating with a Turbo-Till, and that has worked really well for us. Once we get that down, we just keep hammering away at it. One thing we might have made a mistake on is that when we went with Flex, we pretty much threw our hoods in the garbage and didn’t do any layby or anything for awhile.
“But we started going back to that. We’ve taking advantage of the incentive program for hoods, and we try to do a better job with our layby,” he says.
Resistant Palmer pigweed is a “nightmare,” says Newby, and growers should do everything possible to stay ahead of it. “You’ll start out with a small spot. The next year, it’ll be as big as a pickup truck, and the next year it’ll be as big as a trailer. Once you get on it, don’t let up,” he says.
Bill Webster, a consultant in Alabama and Tennessee, says it was about four years ago when he decided he probably had a problem with resistant pigweed. “We had escapes that first year. Then, the next year — about three years ago — we planted cotton, put down Prowl, let it get activated, came back twice with Roundup, and still had pigweed. We killed a few with Staple, but most of them survived and we ended up topping them out. The next year — two years ago — we planted in wheat and then came back with soybeans, double-cropped, and put out the pre-emergence,” he says.
When rain finally did arrive, says Webster, the pigweeds came up. “Once they get any size on them, you’re not going to get rid of them. This year, we noticed that the combines and other equipment spread them to more fields. You can tell where the equipment pulled into the field. There may be a streak of them or they may be scattered in the field,” he says.
Webster says he’ll be advising growers to do more incorporating of yellow herbicides. “We just need to stay on top of them. I don’t think we’ll ever eliminate them,” he says.