Through late April, the Mid-South has experienced an abundance of warm, dry weather. While it has allowed much early cotton planting, suspicions are that it’s also contributed to weed burndown problems. And early-season pest concerns are also popping up.
“I’m as busy as I’ve ever been,” says Larry Steckel, veteran Tennessee Extension weed specialist. “This has been, by far, the most frustrating spring we’ve had. It’s been tough to burn down weeds in general, but (glyphosate-resistant) horseweed in particular.”
Products that normally work well aren’t doing the job. “Usually one of the standards, or a combination of them, provides 95 to 99 percent horseweed control. Not this year.
“We’ve got a number of counties — particularly along the Mississippi River — with extremely inconsistent results. There is re-growth in many fields. Producers are returning with either Gramoxone or Ignite with a pre behind the planter. We’re getting into $20 to $30 burndowns. Basically that’s to control resistant horseweed. It’s been very frustrating.”
Steckel believes much of the problem is linked to the atypical spring weather. “It was 80 and 90 degrees in early April with very dry soils. The herbicide activity was poor. To me, it appears we may have lost some dicamba through volatility. Hot, dry conditions would enhance that problem.”
What does this portend for the rest of the season?
“If we can’t finish off these stunted plants, it could be trouble. I’ve walked some Tipton County and Lauderdale County fields where there are easily 20 horseweed plants per square foot. It’s a carpet. Even with 90 percent control, that’s one or two per square foot — plenty to cause us trouble.”
Burndown problems aren’t being seen across all of west Tennessee, but Steckel says they aren’t hard to find. “The middle portion of the state hasn’t had many weed problems. The counties toward the Tennessee River have better control and soil moisture has been better.”
Some 5 percent of Tennessee’s cotton has been planted. “A percent or two is out of the ground,” says Scott Stewart, Tennessee Extension cotton IPM specialist. “We had a little bit planted around April 12. It was very warm then. But most were still planting corn and soybeans in that window. They weren’t ready to plant cotton and that’s normal. Tennessee cotton normally goes in from the last week of April through mid-May.”
In late April, “quite a bit of rain came. Now, even if producers wanted to plant, it’s too wet. And there’s more rain predicted along with cool temperatures. We’re looking at marginal planting temps — highs in the 70s, lows in the 40s. My guess is most Tennessee cotton farmers will hold off planting (into the first week of May). That’s assuming it stays relatively dry.”
Louisiana is the only Mid-South cotton state not reporting problems with horseweed burndown. Half the state’s cotton has been planted.
“With the latest rains, moisture is no longer a limiting factor,” says Sandy Stewart, LSU cotton specialist. “Once it dries up enough for farmers to get back into the field, I think the last half of the planting will go quickly. The forecast says it’ll warm up (the first week of May).”
Stewart has heard of very little replanting. “The reason is we’ve had an unseasonably warm April. Normally, cool weather is a limiting factor in April. This time around, moisture was the limiting factor.”
Beginning in mid-April, a few reports of false chinch bug outbreaks began reaching Stewart. Most were in no-till operations with lots of residue. “This is a difficult insect to control so everyone needs to be looking out for it.”
Bill Robertson knows some Arkansas cotton producers that are already through planting. “It’s awfully early, but planting is really cooking,” says the state’s Extension cotton specialist. “South Arkansas is probably 60 to 65 percent done. The central portion of the state is a little over a third planted. The northeast is further behind. I bet we’re not more than 10 to 15 percent planted there. That’s not due to temperatures but lack of moisture. Some wheat and corn in that area has been beaten up.”
The latest rains are very welcome, says Robertson. But they’re not going to replenish the deep moisture the state is lacking. “One or two storms aren’t going to bring the subsoil moisture up to par. Without timely rains this season, it’ll make life challenging.”
Robertson has gotten calls from producers “who thought they had horseweed under control and found out they didn’t. It’s definitely causing headaches. There are also calls already coming in to (Extension) entomologists on pests. That’s not a good omen.”
Mississippi cotton is about 40 percent planted with much of the Delta crop in. The state’s hill area “has a few acres planted but they usually don’t really get going until after the first of May,” says Tom Barber, Mississippi Extension cotton specialist. “After the recent rains, I’ve seen seedling disease on some acreage that wasn’t treated with a fungicide. The cool snap we’re in now isn’t going to help.”
Barber reports horseweed control problems in the state’s north Delta counties. Burndown products “have beaten it up but haven’t killed it. There are a couple of places where the producers have decided to switch to Liberty Link. The only way to hold it back until the crop canopies is with Ignite.
“In order to kill resistant horseweed that’s overwintered, we have to hit it early. Producers need to get after it in mid-February. The root system of that plant is as big as a carrot and it’s hard to kill. The farmers who did spray early have had much better burndown results.”
In the Missouri Bootheel, around 30 percent of the cotton is planted. “Producers are in the field early up here,” says Mike Milam, Dunklin County Extension agent. “I drove though the Clarkton area (on April 26). Even though severe thunderstorms had come though the evening before, there were still folks planting.
“(On April 26), I was visiting with some folks working in the boll weevil eradication effort. They already have reports of cotton at first true leaf so they anticipate the pinhead square application will go out in late May.”
Many Bootheel farmers have already turned on their sprinklers. Milam says wheat fields have even been watered in the Malden/Clarkton area.
The Bootheel has also seen trouble with resistant horseweed. “I’ve had calls asking what could be used to get rid of it. The problem is it’s almost too late. They can still use a couple of products but that could cause a delay in planting. There are some tough decisions being made.”
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