There's a young revolution going on out here in the lush farm country of southwestern Iowa, and Max H. Miller is at the fore of it.

Miller, 63 years old going on 40, hasn't used a plow on his land since 1969. But he raises several hundred acres of corn and soybeans every year, getting yields and cost savings that would make most tradition-bound farmers drool.

Farming without a plow is becoming commonplace in Iowa. Farmers are abandoning the standard moldboard plow, a basic tool of American agriculture, for radical new cultivation techniques in an effort to stem the spectacular erosion of the state's rich topsoil.

Iowa is a textbook case of the best and the worst in erosion control. It loses more topsoil to erosion than any other state. But many of its farmers, like Max Miller, are rapidly altering their farming practices to stay ahead of the erosion that threatens their livelihood.

About half of Iowa's cropland was tilled without the plow last year. The national figure is perhaps 20 percent. But the question is whether farmers can do enough, quickly enough, to keep the best part of the country from washing to the Gulf of Mexico. Much of Iowa is gone already, floating and blowing away at a rate of 261 million tons a year.

"Erosion control is very critical if we are going to continue to produce the food we need," said Gov. Robert D. Ray, the country's most outspoken governor on soil conservation. "You can only mask the problem for so long. Much of the public still thinks food is manufactured by the chain stores.

"A third of our Iowa land is protected, but our losses still average near 10 tons per acre annually," he continued. "I feel we are not doing enough here, yet we are the national leader in conservation work. But there is a different attitude and awareness now than there was 10 or 15 years ago, and sometimes that gives you hope."

Iowa, the second most important farming state in terms of income, ranks first among the 50 states in soil erosion losses--an average of 9.91 tons per acre of cropland, more than double the national rate. On unprotected slopes, like those in this part of the state, two bushels of topsoil are lost for every bushel of corn that is grown. The national average soil loss rate, according to the U.S. Department of Agriculture, is just below the "tolerable" level of five tons per acre annually. Erosion on 143 million acres of farmland is well above the acceptable level, and millions of acres more are reaching danger levels.

"We had the old persistent problems and we were making progress in solving them in the last decade," said Norman A. Berg, head of the Soil Conservation Service at USDA. "Then came the new pressure for production and then the drought, and we have 413 million acres of cropland under heavy strain in the last several years. A fourth of this cropland suffers serious soil loss."

In Cass County, where Max Miller farms, and in 15 other western Iowa counties--all characterized by highly eroding soil on rolling hills--losses of 30 to 35 tons per acre are common. During three driving summer storms in 1980, the loss rate in Cass County reached 150 tons per acre, almost unheard of.

"The loss of topsoil is, in a sense, short-term mining," said Rollin N. Swank, SCS's deputy state conservationist. "Farmers out here have covered their soil losses with the use of nitrogen. But costs go up, the land is harder to work, yields fall, drought affects the crop. There is a day of reckoning."

Since the time of Thomas Jefferson, who invented a version of it, the moldboard plow has been the vital to American agriculture. The great western prairies could not have been opened without it. Much of today's high productivity is related to the plow, which turns the soil, helps warm it and moisten it, rejuvenate it and ready it for planting.

But in anothersense, the plow is destructive. Fall plowing after harvest, a custom in most parts of the country, exposes loose soil to erosive wind and water. In combination with an increase in high production row-cropping--the planting of corn and soybeans in long, erosion-prone lines, for example--the tensions on the soil mount.

Many farmers have understood this for years, but tradition and habit die hard in farm country.

Some plow in the fall because their soil requires it; others plow in the fall because their fathers and grandfathers did. Some simply feel a compulsion to be in their fields. Others are sensitive to neighbors' criticism about "sloppy," rubble-strewn fields, so they plow.

Attitudes, however, are changing rapidly. The word "revolution" is not out of place. Pinched by high costs of fuel, fertilizer and equipment, and driven by worry over soil erosion losses, farmers are looking at new and more economical forms of tillage. None of them involves the plow.

"I think we're just seeing the beginning of a real revolution in farming methods," said William Brune, the SCS state conservationist for Iowa. "Of the 27 million to 28 million acres of cropland in Iowa, we estimate that about half no longer are tilled with the moldboard plow. Conservation tillage is catching on. There is a groundswell."

These new farming systems go by different names--no-till, minimum tillage, conservation tillage. They involve varying degrees of mild soil disturbance or none at all; chemicals to control weeds; the retention of residue from previous crops to hold surface moisture and the use of specially designed planters that cut through the residue to deposit seeds in the earth.

No-till, the least erosive of the cultivation techniques, was used on more than 220,000 acres in the state last year, double the previous year's figure.

"We're seeing more and more farmers leaving more residue on the fields, making less trips across the fields. They're saving time and fuel and soil," Brune said.

Arnold King, a tillage specialist with SCS in Washington, said: "All the research on conservation tillage shows that farmers can get a higher yield or they have potential for higher yield. The secret is learning to manage the moisture. Good farmers make conservation tillage work. The failures are usually with farmers who are not good farmers in the first place."

Conservation tillage practices alone do not assure an end to erosion. Expensive terraces and drainage networks also must be used on some sloping land to control water runoff. Strip cropping and contour planting must be used on other land to help hold soil in place.

William E. Willis II, the SCS conservationist in Cass County, said, "Tradition and the cost of making changes are deterring some people. There is enough information and knowledge on conservation tillage right now that a farmer can make it work if he wants to.

"But one thing concerns me," Willis said. "There is a lot of interest in this, but it still won't bring soil loss down completely without contour strips or contour terracing on much of the land above a 5-6 degree slope. If we can get conservation tillage on a majority of the land until we can get to the terracing that needs to be done, a lot of the topsoil will be left."

Changes in cultivation techniques are seen also as a relief valve on the demand for federal and state conservation assistance money, which is in short supply. Iowa, one of the few states with its own conservation cost-sharing program, puts up $6 million of its own annually and gets $7 million more from Washington for cost-share arrangements. The demand for the money is high.

"We've built the interest out here, but the problem is money," Willis said. "Terracing is very costly--it costs about $500 an acre in Cass County--and we're short of money. This year we were $51,000 short of money to cover the applications we received. The farm economy is so bad, these guys can't do the work on their own." get this conservation job done until it's mandatory. So many people don't care," Miller said. "Greed is one word that fits in here. These farmers know what they're doing to the land. They say they can do as they please. The job for some would be easier if we got a fair price for our crops, but in the end we are stewards of this land. Hopefully I'll leave it better than I got it."

He wasn't talking about young Brook Tanner, another of the cultivation revolutionaries who works 1,360 acres across the county. Tanner tries to spend some money every year building or repairing conservation structures.

This winter he's had three bulldozers building terraces and smoothing waterways for grass planting on one of his parcels. The slopes are smaller, of course, but the place has a look of the pre-Hispanic Andes --heavily terraced, carefully cultivated and husbanded.

"We plow nothing on this farm. It's all minimum tillage," Tanner said. "A lot of farmers just don't want to take the time to farm around the terraces. They really don't know what it's about. I don't plan to sell. I might as well take care of it."