Fighting Dust With Dust

PULLMAN, Wash. — Foresters have long fought fire with fire, so why not fight dust with dust?

That’s just one of the ideas being pursued by federal and state scientists at Washington State University engaged in research to help farmers reduce wind erosion and improve air quality.

Bill Pan, chair of the WSU crop and soil sciences department, reported at a recent project review meeting in Spokane that scientists are studying the feasibility of spraying irrigated fields with a starch-based dust made from potato byproducts to combat blowing dust.

Other research involves controlling wind erosion by dusting fields with a compound consisting of lignin, carbohydrates and ash minerals reclaimed from a straw pulping process.

“This is the first year of testing the lignin-rich pulping liquor from wheat straw,” Pan said. The research is being conducted near Wallula Gap southeast of the Tri-Cities.

These and other ideas were reported at the 10th annual meeting of the Columbia Plateau Wind Erosion/Air Quality Project.

The program, administered by Washington State University and USDA’s Agricultural Research Service, presently includes 16 funded projects, including some at the University of Idaho, the University of Oregon and Oregon State University. Scientists at the Washington State Department of Ecology, the Environmental Protection Agency, Natural Resource Conservation Service and several local, state and regional grain grower groups play key advisory roles.

The project covers the low precipitation areas where blowing dust is a common problem. Bill Schillinger said this involves three million acres of cropland in Washington and 500,000 in Oregon, mostly in areas that receive less than 12 inches of moisture each year.

Schillinger says research shows that the region’s dust problem isn’t simply a matter of soil being redistributed from one field to another. Fine particulate becomes suspended in the air and may travel thousands of miles. “We’re truly losing soil. It’s gone,” he said.

“We’re dedicated to measuring what’s going on, helping farmers stay in business and keeping soil where it belongs, right where it is.”

Mark Weltz, USDA-ARS, Washington D.C., said agriculture accounts for only 19 percent of the nation’s PM10 pollution, yet farming is coming under increased scrutiny by the Environmental Protection Agency.

PM10 is particulate matter 10 microns and smaller.

Even as researchers work to help farmers comply with PM10 standards, the EPA is developing rules for a PM2.5 standard — 2.5 microns — amid growing concerns about health effects of “fine” particulate matter.

Weltz said diesel exhaust is a primary source of PM2.5 and farming operations that involve diesel powered pumps and equipment will be affected by the standards now being considered.

Dave Lauer, Benton County Air Authority, predicted that a PM2.5 standard will replace the current PM10 standard. He also believes agriculture will be caught up in diesel’s contribution to air pollution throughout the United States.

Diesel emissions account for 80 percent to 90 percent of toxic emissions, Lauer said. He believes new EPA rules will place greater emphasis on toxic pollutants. The federal government classifies 188 compounds as toxic air pollutants, of which 33 are on a priority list for action. Washington State lists 500 toxic pollutants of concern in air quality.

Also being developed by federal scientists is a new model for wind erosion prediction as scientists continue to struggle with an imperfect knowledge of chemistry involved in generation, detachment and transport of dust particles.

Among other things, research is aimed at developing more reliable instrumentation.

Mark Sweeney, a Washington State University geologist, said we live in a period of rapid fluctuations in climate. His research is aimed at understanding “the big picture.” Sweeney is using luminescence dating — a radiometric technology that dates the last time that a mineral grain was exposed to sunlight — to study 18,000-year-old dust fluxes.

Sweeney believes understanding past climatic changes will help scientists predict what will happen in the future, and thus guide scientists’ research on dust control.

Reporting on flex cropping and chemical fallow potential, WSU’s Claudio Stockle, a biological systems engineer, cautioned against extrapolating on one year’s experience, or even on a few years’ experience.

Stockle said computers have vastly speeded research. Scientists now can get data in five seconds that used to take them a day and a half.

Paul Scales, Natural Resources Conservation Service, touted the 2002 Farm Bill as the “single most significant commitment in history of resources towards conservation on private lands.”

Instead of protecting land by taking it out of production, Scales said the new farm bill emphasizes the health of land in production. Scales said the farm bill authorizes a $9 billion increase in funding for environmental quality; but, he cautioned, the money will become available only if Congress appropriates it.

The bill also provides for flexibility in decision-making at the local level and increases the limit on payments from $50,000 per person to $450,000 over the life of the bill.

Scales said the bill includes air quality as a purpose in the law for the first time and expands accessibility.

“I think it’s going to be an exciting program,” Scales said of the new farm bill.

Pan reported on research that combines satellite radar images with LANDSAT photographs. Scientists have discovered that overlaying the two images allows them to separate types of ground cover.

Pan showed combined images of the Quincy area, which researchers are now analyzing. He said scientists in his department are developing a Web site that growers will be able to use to evaluate cover crops with graphic information systems technology.

In a presentation on the economics of wind erosion control, WSU Agricultural Economist Douglas Young cited the example of Horse Heaven Hills farmers, who grow wheat on the driest crop land in the world.

“The farmers there are as tight-fisted as you can be,” he said. One of their strategies is that of extending equipment life as far as they can.

“Squeezing the costs is the key to survival,” he advised.

Young’s studies show that even Horse Heaven Hills farmers can break even using a winter wheat-summer fallow rotation, but not continuous annual hard-red spring wheat. “Break even isn’t bad when you’re covering costs, labor and return on equity,” he said.

Jerry Snyder, a fourth generation grower who farms near Ritzville, crops 2,000 acres a year. He has 250 acres that have been in continuous no-till since 1990 and has tried no-till on 80 acres of extremely sandy soil.

Snyder who does both no-till and minimum-till, said he tries to limit himself to five operations–harrowing, chiseling, applying chemicals, cultivating and fertilizing in a single operation, and rod weeding. In each operation he tries to leave as much residue as possible on the surface.

“I want a minimum of 750 pounds of stubble per acre,” Snyder said. He has had as high as 2,250 pounds.

Snyder and others at the meeting, appealed for better regulatory standards.

The Wind Erosion Equation that guides conservation programs simply isn’t applicable outside the Great Plains where it was developed, Snyder said. “It’s not transferable.” He said Washington growers need new soil surveys and local control over their use.

Ed Skidmore, USDA-ARS, Manhattan, Kansas, said USDA is addressing the problem.

Frank Berg, who farms near Patterson in the Horse Heaven Hills south of Prosser, spoke of the challenge of farming land that his grandparents settled in 1934.

“Being in the Horse Heavens, we’re almost always in a drought,” Berg said. Winds often blow strong.

He told about his parents’ experience with dust. They bought a new car and on a trip to town in a dust storm, all of the paint was blasted off of one side of the car and both the engine and transmission were contaminated with sand.

Berg gave moisture figures that prove there have been some good years on his farm in the past. But this winter, Berg’s operation struggles with the fifth consecutive year of drought. Berg said his seed was still in the dust during the first week in December.

He is buying straw and applying it to his fields in an attempt to hold the soil.

“The worst enemy of the farmer,” Berg said, “is his emotions.” And one of the worst things a farmer can do is begin plowing when he sees a neighbor plowing.

“To do nothing has been a positive decision, and I’ve done a lot of that this year,” Berg wistfully lamented. He is spending more on chemicals and staying out of the field, except for chiseling. Berg said he’s had no erosion this year on his chiseled land.

Berg said one of his greatest problems is figuring out when a drought has begun so he can adjust his operations.

He currently has a third of his crop land in the Conservation Reserve Program. He and Snyder agreed that without farm payments, they would be out of business.

“What growers really want is continued research on crop related systems that help them farm better,” said Bill Schillinger, WSU research agronomist and co-leader of the project.

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