Houston — Just when many programs launched by Franklin D. Roosevelt risk being discarded, one New Deal idea is gaining new ground on farms from Texas to the Dakotas.
Planting rows of trees to break the force of wind whipping across flat cropland was first used on a massive scale in the United States in the 1930s. Now it's coming back into fashion with the realization that Americans can't afford to continue wasting a precious natural resource - topsoil.
Building new windbreaks benefits both farmers and the public, US Department of Agriculture officials explain. A recent USDA report concludes that windbreaks ''protect land from wind erosion; shelter livestock; provide nesting and cover for wildlife; give blizzard protection for all creatures; make pleasant and attractive surroundings for farmsteads; and trap dust that would otherwise pollute the atmosphere.''
A 1981 USDA report on farmstead-windbreaks estimated energy savings of 10 to 30 percent - or a potential saving of 221 million gallons of fuel oil annually if another 20 percent of unprotected farm-belt farmsteads added windbreaks.
Despite the USDA's pro-windbreak stance, however, some farmers are ripping out windbreaks. B. L. Harris, a Texas Agricultural Extension Service soil specialist, sees this as a natural trend. He says that modern conservation tillage techniques have reduced the importance of windbreaks. Dr. Harris adds that government-backed windbreaks have been used to produce crops on ''land that should go back into grassland.''
Conservationists warn that more windbreaks may be removed to create larger fields for today's huge tractors and center-pivot irrigation systems.
Neil Sampson, a former USDA soil expert and now vice-president of the National Association of Conservation Districts, is a strong advocate of increased government support for windbreaks and other conservation programs. With farmers caught between low prices for farm products and high costs, Mr. Sampson explains, ''The farmer is forced by economics to wring the most cash out of his property that is possible and, with interest rates and operating expenses soaring, that includes plowing up windbreaks.''
Even a farmer who knows the long-term value of windbreaks, Sampson says, may rip them out because of his immediate need to meet bank payments. The result, he says, is that ''there is a lot of cropland opened up that shouldn't be, which increases the amount of dust in the air and increases the sandpaper action which air-blown dust has, in turn creating more wind erosion and crop damage.
South Dakota grain farmer Ed Hofer is convinced of the value of windbreaks. He says his farm's windbreaks have been well tended for 50 years and are going to stay. ''
If our neighbors started taking out their windbreaks,'' he says, ''we'd be going back to the '30s, where there was nothing stopping the wind at all.'' He explains that it takes hard work to start a windbreak and that a windbreak means putting about five acres of cropland in trees to protect a 160-acre field.
But Mr. Hofer figures that ''over the years, the better grain production alongside the windbreak will make up for the land lost.'' He says he is also saving precious soil from wind erosion. This winter's blizzards, he adds, showed how well his windbreaks work: ''We went over behind that windbreak, a quarter of a mile away and the wind just dropped down, then picked up again just as we went past the trees.''
USDA district conservationist Monty Gearner doesn't find many farmers in his area, Levelland, Texas, who favor windbreaks. This flat, dry country had bad experiences. Poorly designed windbreaks here in the '30s and '40s built up huge sand dunes. Mr. Gearner says it's hard to win over even young farmers today because of the extra work and expense involved in establishing a windbreak. ''
People trying to earn a living,'' he explains, ''are concerned about losing cropland, so naturally they're stingy about putting in a row of trees.''
But with the USDA giving encouragement, sharing costs, and providing new types of trees suited to local conditions, this 10-county area added 3,000 trees in 1979, 12,000 in 1980, and 30,000 in 1981. Such tree planting is urgently needed, says Budd Fountain, a USDA conservation officer, because ''up on these high plains we've got about 14 tons per acre annual soil loss from wind erosion, whereas five tons is about the most we can stand to lose and maintain soil productivity.''
Gerald Darby, national agronomist with the Soil Conservation Service, and other USDA officials stress that cutting soil loss depends on using a full range of modern conservation practices - particularly for the erosion-ravaged cotton fields of the Texas plains. But Mr. Darby is convinced that windbreaks can be more important than ever, thanks to new techniques. More powerful tractors, for instance, mean farmers can use deep plowing to control tree roots. Computers can match new tree varieties to particular soil and weather conditions.
A key development, explains the USDA's national forester, Robert E. Hartung, is narrower windbreaks with just two or three rows of trees. The USDA is increasing windbreak planting programs, he says, because ''with our new techniques we can get better results than before while using less cropland, which means less cost to farmers.''
One Texas farmer already won over is Virgle Simmons, who manages 2,000 acres of cotton and corn in Lubbock. He has planted 1,000 trees to control wind erosion on a 177-acre field. The experiment has cost him $5,000, long hours of hand-watering his trees, and ''10 acres of cotton.'' If this first windbreak works out well, he's ready to plant more and says ''there's quite a few neighbors watching to see how it works out for us.''