Texas High Plains cotton farmers have caught few breaks this year, but light late-season insect pressure may help some contend with the frustration of the crop that could have been.
“We seem to be in a typical pattern for the region — early spring moisture and then not enough timely rain in mid to late summer to finish the crop,” says Brant Baugh, Extension Integrated Pest Management Specialist in Lubbock County.
“Fortunately, late season insect pressure has been light. We're seeing some whiteflies moving into cotton as nearby sunflowers dry down.”
He says worm populations have teetered on the verge of treatment levels at times but have not caused serious damage.
“With the hot, dry conditions, worms may reach worrisome levels but in four to five days they're gone. It doesn't pay to spray under these conditions.
“Mostly, we're seeing nickel and dime damage, and if cotton were selling for 70 cents a pound, farmers could justify insecticide applications — but not at current prices, especially when they know the pests will be gone in a few days.”
He admits to some concern about sticky cotton from whiteflies. “If farmers find 75 to 100 whitefly nymphs on the fifth true main stem leaf from the top, they may want to apply something,” Baugh says. “They should check 50 or 60 leaves and take the average.”
Baugh says a combination of a pyrethroid, at a mid-rate level, and Orthene, at about nine ounces, should take care of whitefly problems. Treatment costs will run from $11 to $14 per acre. “With aerial application, consider $14 to $17 per acre,” he says.
Thrips crawled to the No. 1 pest problem early in the season, Baugh says, ahead of leafhoppers.
Low cotton prices may make late-season insecticide applications difficult for many farmers to justify, especially during a prolonged drought. “Many producers will not spend more than $9 per acre this late in the season,” Baugh says. “Fortunately, the crop is almost out of the woods as far as worms and boll weevils are concerned.”
He says growers should decide early in the season how they intend to approach late insect pressure. “First, they must know their cost of production and, unfortunately, many do not. But this year, bankers are making a lot of the late season production decisions and may cut off funds for late insect control.”
Baugh says if farmers have protected a crop up to a certain point, he can in most cases still justify subsequent insecticide applications.
“We rarely run into a situation where a producer protects his crop and then backs off. The deeper he gets into protection, the more likely he is to stay the course.”
Baugh says an early game plan may be to protect the squares and let the boll crop go. “In the Texas High Plains, if we lose squares, we can't make them up. The norm may be to get an 80 percent to 90 percent square set and then cut off treatments.
“If a farmer detects 30 percent boll weevil punctures and makes three insecticide applications and decides not to make a fourth, even though it's necessary, he did not help himself with those first three sprays.”
Baugh says a good benchmark is to assume cotton will not make a top crop after plants reach the four-nodes above the uppermost white flower stage with 450 to 500 heat units accumulated.
“Farmers should decide early how they want to protect their crop. It's cheaper to control early-season pests and early applications save squares. But if they begin to protect bolls, they're committed.”