Drought takes toll, however

Alabama cotton insect pressure down Even in a light insect year, and using technology that requires less pesticide use, many Alabama cotton producers will struggle this year to make a profit, due primarily to severe drought conditions. It's enough to make some question the future viability of dryland farming.

"Many of our growers simply can't continue to gamble on dryland cotton," says Ron Smith, Auburn University Extension cotton entomologist. "If we look at the next five years, three out of five of them probably will be losing propositions for many of our state's growers."

Real problems After several consecutive poor crop years, most Alabama producers don't have the capital to invest in irrigation, notes Smith. "We've got small, irregular shaped fields and, in many areas, no water source. On some farms, growers would have to dig 1,000 feet down to a water source," he said during a recent cotton tour in drought-ravaged east Alabama.

If growers can afford irrigation, they might want to consider farming only their best land and reducing their total acreage, says Smith.

"Rather than growing 1,500 acres of dryland cotton, they might want to take a look at growing 400 acres of irrigated cotton, doing the best job possible and insuring a yield of two to three bales. Or, maybe they could take a look at some other high-cash crop," he says.

"We just can't get the costs down enough so that growers can make a profit under these erratic weather conditions. The money invested in a cotton crop is so great, we can't afford to have a disaster - it's just not an option."

Most growers have reduced their production costs by changing their tillage practices and by not spraying as many insecticides. "Many producers are growing Roundup Ready cotton, but they're not planting Bt varieties. They've reduced their costs, but they still can't make a profit," he says.

Insect review Also during the east Alabama cotton tour, Smith reviewed the state's insect pressure throughout the 2000 growing season.

"Insect pressure has been very light throughout Alabama for most of this year. That's pretty much the statewide picture with the recent exception of conventional cotton along the Gulf Coast," he said in early September.

"They're spraying cotton with a $12 Tracer application about once per week because they have bollworms, budworms and soybean loopers. Everything is attracted to late-planted or irrigated cotton in that part of the state."

Because of either back-to-back dry years or recent changes in tillage practices, Alabama growers now are seeing many unusual insects at the beginning of the growing season, says the entomologist.

"We sprayed a lot of acres in central Alabama for grasshoppers at about the time cotton was emerging. They were in fields by the thousands. We also saw more than our share of cutworms, and we even had vegetable weevils cutting down cotton plants in one area."

Thrips pressure Thrips also were very heavy in Alabama this year, he says. "You might not have noticed it unless your hopper was stopped up, but we experienced heavy pressure this year from thrips."

Plant bug pressure also has been very light throughout 2000, says Smith. "This is because they come off of wild host plants from the borders of fields in May. Plant bugs didn't have a chance to move into the fields this year because May was a very dry month. Later, we experienced some high levels of flea hoppers in several places in Alabama, but they're not as damaging late in the season."

Bollworms and budworms were practically non-existent throughout most of the growing season, he says. "We saw a little pressure during the first part of August. But to my knowledge, there were very few bollworm escapes on Bt cotton. We did have enough pressure to spray conventional cotton in most areas during this time."

As the growing season progressed into August, pockets of Alabama saw high numbers of soybean loopers. In some fields, growers found as many as 80 loopers per six row feet, says Smith.

"Such a high number of loopers will eat all of your foliage in about 10 days. We consider about five per row foot to be a threshhold level for spraying. One chemical - Tracer - will do a respectable job, at a full two-ounce rate. And loopers aren't just attracted to irrigated cotton - they'll also hit a dry field."

Not all of the factors were present this year, he says, for an outbreak of beet armyworms. "Several things contribute to beet armyworms. It's almost as hot and dry as it has ever been in Alabama, and the moths have been here. We've caught a lot of beet armyworm moths, but we haven't seen any outbreaks.

"In addition to heat and drought, you've got to have intense phosphate insecticide use occurring at the same time. That's the third factor required for creating a disaster."

Fewer worms Worm problems have been reduced in Alabama because so many growers have changed their tillage practices, he adds. "This is saving our growers a significant amount of money."

Aphids lingered in many Alabama cotton fields for several weeks this year, says Smith, and many growers invested a lot of money to control them.

"A couple of products will control them. One of them is Provado, and it's about the only consistent product. It's tank-mixed with a pyrethroid called Baythroid and a product called Leverage. If you don't need a pyrethroid, the combination won't be as effective as Provado alone.

"In our tests, the pyrethroids killed the beneficial lady beetles, but the lady beetles were surviving the Provado alone. For future years, it's fine to treat aphids, but don't use the tank-mix unless you need a pyrethroid."

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