June 07 2017
Cotton’s effect on the environment continues to diminish
Cotton’s environmental footprint is much less noticeable today than was the case in the early 1960s, thanks largely to science and technology.
Ryan Kurtz, director of agricultural research, Cotton Incorporated, says the highly successful Boll Weevil Eradication Program, genetic engineering, innovations in tillage, and changes in farm size and efficiency combined to reduce cotton’s impact on the environment over the past 35 years.
Kurtz, addressing a group of textile manufacturers, retailers and trade journalists during a recent Cotton Incorporated conference—“Everything You’ve Heard About Cotton is Wrong”—in New York City, said cotton farming has evolved from “horses to robots and drones. We’ve seen great strides in reduced soil loss, water use, and pesticide use.”
Those environmental benefits also help farmers, Kurtz added. “Farmers have a balance sheet, and their goals are to maximize yield and minimize costs. They will not spend money they don’t have to spend.”
Those environmental improvements have not been at the expense of production. “From the ‘60s until now, cotton farmers have almost doubled the amount of cotton they grow with no more acreage. Science and technology make that possible.”
He said commercial cotton breeding has created new varieties that produce more lint. Integrated pest management (IPM) programs allow producers to be more precise in targeting insect pests, he added. And those pesticides are more selective, targeting specific insects, diseases or weeds.
Kurtz said reduced tillage systems conserve moisture, increase organic matter in the soil and limit water and wind erosion. “We’re doing a better job of protecting our soil,” he said.
“Biotechnology now protects plants from insect damage,” Kurtz said. Herbicide tolerant varieties also allow a more efficient weed management system. “Cotton farmers also reduce energy consumption because of biotech,” he added.
“Genetic engineering has improved varieties in other ways. We have more water efficient varieties,” which improves on a plant already known for drought tolerance. “Cotton requires significantly less water than corn, wheat and rice.” Only a small portion of U.S. cotton production receives full irrigation, he adds, and most gets by well on supplemental water.
“We have improved water efficiency in the past 35 years,” Kurtz said. Better varieties play a crucial role, “but sensors improve efficiency and application timing that works better than just ‘eyeballing.’” Measuring evapotranspiration offers real-time information to help schedule irrigation. “Irrigation timing can be a data-driven assessment.”
SAVING BENEFICIAL INSECTS
Kurtz, an entomologist by training, said cotton farmers once followed a calendar approach to insect pest management, sacrificing beneficial insects in an effort to head off damaging populations of pests. Pesticides were non-selective, he said, and took out lady bugs and other beneficials as well as bollworms and boll weevils.
“Now, we use more selective pesticides to preserve beneficial insects, and we spray when populations reach economic thresholds. That’s the value of IPM.”
He said the success of the Boll Weevil Eradication Program and the introduction of Bt cotton revolutionized insect control in cotton. “At one time, cotton farmers in some areas were spraying as many as 15 times in a season. The average was seven. Following boll weevil eradication, the average dropped to five, and after Bt cotton was introduced the average dipped to two.
“We also have newer, more efficient ways to apply insecticides. Seed treatments, for instance, reduce the need for early (over the top) pesticide applications.” These products are applied to the seed before planting and are systemic, so the roots take them in. Amount of product necessary also dropped. “Instead of pounds per acre, we can now apply milligrams per acre,” Kurtz said.
He said ongoing research considers the possibility of developing cotton plants that repel insect pests.
Kurtz said cotton’s effect on the environment is a lot less than it was three decades ago. “We’ve made progress in reducing our environmental footprint in the last 35 years,” he said. “And we will continue to do that.”
Source: Southwest Farmpress