It has been a season filled with contrasts for many farmers in the lower Southeast this year, with extremely dry conditions at planting and plenty of rainfall in July, only to be followed by more drought conditions as the year progressed.
Drought continued to intensify in the region during August, as Hurricane Irene bypassed states that needed rain the most.
These growing conditions made it easy to distinguish between the “haves” and the “have-nots” of irrigation during the Central Alabama Crops Tour held in mid-August.
Robert Walters, who grows peanuts and cotton in the area, says the only thing he hasn’t liked about his irrigation scheduler this year is that it hasn’t told him “no.”
“Our irrigation water comes out of a lake, and we use IrrigatorPro for scheduling irrigation. There were times when it didn’t appear as if it needed watering, but it was running out below the surface.
“If rain didn’t give us at least 6/10-inch, I’d just keep the irrigation running. We try to run it in the evening, from 6 p.m. until 7 a.m.,” he says.
Walters also uses the irrigation scheduler for his cotton, which yielded almost 1,000 pounds per acre in last year’s drought conditions. “We put irrigation out for a reason — it’s not to hang Christmas lights on,” he says.
Alabama peanut producers with irrigation certainly have benefited this year, says Kris Balkcom, Auburn University Extension peanut specialist.
“Peanuts only grow vines until they are about 100 days old, and then they start slowing down. If we’ve got the water, we need to go ahead and close in that canopy and keep back the weeds.
“It’s important to keep the soil cool. IrrigatorPro has been proven to make the highest peanut yields when using it to schedule irrigation,” he says.
It’s important in a dry year, says Balkcom, to get peanuts off to a good start.
“After a one-inch rain, when the environmental conditions have changed and it’s cooled off, come back the next day and put out another inch. Make those peanuts good and wet in the soil profile. Then you can maintain them on a weekly basis throughout the remainder of the season,” he says.
While U.S. peanut acreage is down this year — down 10 percent in Alabama — pricing opportunities appear promising, he says. “Peanuts that were not contracted last year that went into the loan are being brought out at $750 to $800, so that gives a little more incentive for growing peanuts,” says Balkcom.
Austin Hagan, Auburn University Extension plant pathologist, says his state’s peanut producers have been spared the worst of disease problems this year.
Little leaf spot
“Because of weather patterns, we haven’t seen much leaf spot. We have seen some white mold in south Alabama, but there isn’t any tomato spotted wilt virus out there. It has pretty much dropped off the map in Alabama in the last three to four years,” he says.
Normally, cotton producers don’t see many foliar disease problems, but that could be changing, said Hagan during the central Alabama tour.
“Over the last few years, there have been issues with potash-related leaf spot diseases in cotton. There have been fungicide trials to try and manage that issue. Basically, if you bring up the potash level, you generally won’t have a problem with leaf spot,” he says.
However, corynespora leaf spot disease has been a problem in Georgia for the past three or four years, particularly in irrigated, no-till cotton, when cotton follows cotton, he says.
“It’s hard to judge how much yield loss might be occurring. But if leaves fall off where squares or bolls are developing, the boll won’t get any larger. It does appear this disease may be an issue.
“We have received samples with moderate to high levels of leaf spot. It has particularly been an issue in Baldwin and Mobile counties, where in isolated fields we’ve already seen 25- percent leaf loss on plants with four or five bolls,” says Hagan.
With dryland cotton, this disease probably won’t be an issue. “One of the problems is that there virtually has been no work done on this disease, other than demonstration plots in southwest Georgia. We’re trying to develop a profile on the disease so we can do some work on it next year,” he says.
Assessing the cotton insect situation in Alabama this year, AU Extension Entomologist Ron Smith says cotton planted from about April 15 to May 15 saw tremendous thrips pressure. It was due mainly to the drying down of wild host plants around the field, along with wheat.
With the loss of Temik still a possibility, he says, early season insect programs will have to be refined.
“As far as plant bugs, nothing happened because dry vegetation around fields couldn’t support a plant bug population,” says Smith.
“But around June 23, we started picking up adult plant bugs in central Alabama. We had a big influx of adult plant bugs in a very short window. I thought we’d see the offspring of those about three weeks later, but it never materialized, and we haven’t seen them since. The heat might have been too much for the immature plant bugs.”
Bollworm numbers low
Bollworm numbers have been extremely low throughout the summer, he says.
Aphids, says Smith, have not amounted to much in 2011. “They are slow to build and slow to crash. We sprayed some cotton because they peaked in late July, and we didn’t need any more stress on the cotton.”
Stinkbugs are by far the most dominant economic insect pest of cotton in the Southeast, he says. “This is the lightest year for stinkbugs since we got Bollgard cotton. But it emphasizes the importance of a scout, even though it’s almost a single-pest system in the Bollgard cotton.”
Resistant pigweed continues to be the dominant weed problem for cotton producers in the Southeast, says AU Extension Weed Scientist Mike Patterson.
“On the conservative side, you’ll probably spend another $40 per acre once you have this weed in your field. We’ve been working with resistant Palmer amaranth pigweed for five or six years now. Last summer, about 24 counties in Alabama reported having resistant Palmer pigweed,” he says.
Growers who successfully manage resistant pigweed are frontloading with a soil-residual herbicide from burndown all the way through layby, says Patterson.
“But they still have escapes, even after they’ve spent about $60 per acre to manage this one weed. Hand labor sometimes is still required. For the foreseeable future, that’s what you’ll have to deal with. You’ll have to use residual herbicides up front, and it’ll probably cost you at least another $30 per acre to use those herbicides.
“You might have to run a hooded sprayer, applying Gramoxone, in those middles, on the escaped weeds. You may even have to go with something like LibertyLink cotton in the future where we can use Ignite herbicide,” he says.
There’s hope in the future, says Patterson, but it’s still a few years away. “Dow and Monsanto both have genetic technology allowing you to spray over-the-top herbicides that normally are very toxic to cotton.
“Dow has 2,4-D tolerance and Monsanto has resistance to dicamba, Roundup and Ignite. But it’ll be three or four years from now before we’ll see the commercialization of those varieties. For the time being, you have to stay ahead of resistant Palmer amaranth.”