WASHINGTON — DAVE SERFLING grows corn and soybeans on a 350-acre farm in Preston, Minn. He uses few chemicals, rotates crops, and hopes to leave his soil as healthy as he found it.
But as Congress undertakes the first major overhaul of farm policy in 45 years, Mr. Serfling worries his attempts at ecological balance could be threatened. Although the House and Senate agree on the basics of agricultural reform - lower subsidies and less regulation - the seven-year House bill would scale back many programs that encourage conservation of fields and wetlands.
As debate begins this week, conservation has emerged as a full-on beltway brawl, pitting cost-cutters and deregulation advocates against hunters and environmentalists, and threatening to hijack the entire farm bill.
For the Republicans, it represents an important test: Will concepts such as smaller government and fiscal responsibility take precedence over earthly concerns like soil erosion and clean water?
''This is daring, landmark legislation,'' Serfling says. ''It could turn out to be a boon, or a boondoggle. If they don't fix the conservation problems, I have concerns. We could be locked into these mistakes for seven years.''
He explains that the current House bill would eliminate a program known as ''Integrated Farm Management'' that has allowed him to set aside as much as 40 percent of his land every year for ''forage crops'' like alfalfa that restore nutrients to the soil and combat insects and disease.
Under the House bill, Serfling explains, he would have to plant 85 percent of his fields with a high-value crop like corn in order to receive his full federal payment - a ratio that would be more taxing on his soil. And as farm payments decline, small farms like his could be forced to work the land harder to compete with less-conscientious farmers.
But Serfling says the worst aspect of the House bill is a measure that would scale back the $1.9 billion Conservation Reserve Program. Established in 1985, CRP pays farmers to set aside highly erodible cropland for at least 10 years. The total enrolled land, about 36 million acres, makes CRP the largest government program affecting the management of private land.
This week's House bill would cut total acreage to 34.6 million, allow no new enrollments, and allow the secretary of agriculture to determine, on a case-by-case basis, whether farmers should be penalized for violating their contracts: a rule that could essentially make conservation voluntary. Similar curbs would be placed on a wetland-conservation program that currently protects about 1 million acres of swampland.
''Things have gotten better in some respects,'' says Chuck Hassebrook, co-chairman of the Campaign for Sustainable Agriculture, citing overall gains in conservation since the enactment of stronger laws in the last decade. ''It's both a credit to farmers and the federal programs. If we eliminate incentives and rewards for conservation, we'll start slipping backwards.''
Even with these programs, some experts say, there is reason for concern. A 1992 study by the Iowa Department of Natural Resources found that in the spring after the first pesticide applications, 98 percent of samples from Midwestern streams indicated chemical residue. And in some counties in Plains states, soil erosion has reached levels not seen since the Dustbowl. With less land in reserve, these problems will likely worsen.
But advocates of the House measure argue that the conservation and rural development programs, which cost as much as $4 billion each year, are too much to bear. ''We cannot stand on the floor and say we want to balance the budget,'' writes House Appropriations Committee chairman Bob Livingston (R) of Louisiana, ''yet create billions in new mandatory spending.''
The bill's author, House Agriculture Committee chairman Pat Roberts (R) of Kansas, argues that as government payments to farmers are scaled back, farmers must be given more freedom from government conservation standards. Farmers are the best stewards of the land, he argues, and giving them more control will improve conditions more than any federal guidelines.
Currently, when farmers sign up for government subsidies, they must agree to abide by standard conservation rules. In forums across the country with more than 10,000 farmers and ranchers, Mr. Roberts says one of the top concerns was rigid regulations.
''Whole counties in Kansas are blowing away right now,'' Roberts says, referring to widespread erosion. ''It's a difficult situation on the Great Plains, so why not give that farmer the freedom to practice good conservation the way his father and grandfather did, instead of this one-size-fits-all mandate?''
Yet the bill has come under fire from a coalition of farmers, environmentalists, hunters, and New York Rep. Sherwood Boehlert, a moderate Republican. He has introduced an amendment that would apply the more-generous Senate conservation proposals to the House bill. ''If we are so short-sighted as to not attach a reauthorization of CRP to this bill, then we are again shooting ourselves in the foot,'' he says. ''In the court of public opinion, we've been clobbered on environmental issues. Now we can prove we've learned from our mistakes.''