Lou Ann Kling is a farmer's wife from Granite Falls, Minn., who in the next few weeks is scheduled to travel to places like Worthington, Pipestone and Wanda, telling farmers how to keep the wolf of foreclosure from the door.

Out in Eureka, Nev., the telephone of rancher LaMoine Addelman, who once worked in a law office, rings constantly. He has become a font of free legal advice for western farmers attempting to keep their heads above water.

Wheat farmer and cattleman Charles Bellman of Wecota, S.D., and his fiancee, Lois Papousek, hold seminars around the Midwest and publish books, a newsletter and tapes with advice for farmers on using bankruptcy and reorganization laws to their advantage.

These are "farmer-advocates," a new kind of activist in rural America. Spawned by the reeling farm economy, all over the country they are working to help fellow farmers weather threats of foreclosure by lenders, principally the federal Farmers Home Administration (FmHA).

Dozens of these advocates, often veterans of their own battles with the FmHA, have joined at least 50 new organizations into a loose network that is learning the rules, challenging FmHA on its own turf and in the federal courts in defense of farmers seeking to keep their land.

And lawyers like Sara Vogel of Grand Forks, N.D., are dusting off Depression-era state laws to argue for farmers' rights in loan-default cases and are pummeling the FmHA with its own rulebook, assuring that farmers are given full, fair hearings before the ax of foreclosure falls.

In state after state, farmers are going to federal court and winning cases in which they allege that the FmHA has deprived them or not advised them of their appeal rights in staving off foreclosure action on delinquent loans.

This new activism is showing up in spite of news from farm country about rising prices, drought-reduced crops and the federal payment-in-kind (PIK) program. The economic crisis that has pushed net farm income to its lowest level in 50 years goes on apace.

Some examples:

* The Department of Agriculture reported 10 days ago that while the amount of land being farmed declined only fractionally from 1982, there are 30,000 fewer farms in operation this year. Sharpest declines were in the southeastern and the east north-central states.

* Liquidations in the farm credit system are running ahead of last year and foreclosure rates in the FmHA are well ahead of last year's rate and double the 1981 rate. About 16,500 farms are in the process of being removed from the FmHA system through foreclosure, voluntary liquidation, sale and transfer.

* The National Grange, National Farmers Union and four other rural advocacy groups charged this month that the FmHA has accelerated the pinch by spending less than half of the money earmarked by Congress for low-interest operating and ownership loans to low-income farmers. They charged that the failure to spend as directed by Congress was a "de facto impoundment."

Much of the new activism spurred by these events is nurtured by the Center for Rural Affairs, a small-farm advocacy and study organization in Walthill, Neb. The center has become a sort of clearinghouse on FmHA issues that publishes handbooks and newsletters telling farmers how they can force the agency to follow its own rules of due process.

"We try to fill an information gap," said Gene Severens, an attorney at the center. "A lot of FmHA borrowers are coming together and working together. In states where there are class-action suits, the organizations rally around the issue. Farmers now know what a class action is; there are a lot of very good lawyers representing farmers now. The movement has taken a life of its own."

"What it amounts to is that we have to go to court to get some decisions to get this thing resolved," said LaMoine Addelman, of the Farmers and Ranchers Protective League. "Judges are going with farmers all across the country . . . . Our aim is to make farmers as aware of this as we can. And we've got more cases than we can handle."

The farmer-advocates find that their legal and financial advice often is as important as the psychological uplift they provide by giving troubled farmers a shoulder to lean on, by convincing them that their problems are not of their own making.

"The psychological side is important," attorney Vogel said the other day. "When farmers go away from FmHA they rarely feel they've had a fair shake. The experience leaves a lingering bad taste. It develops an attitude toward the federal government that is unhealthy."

Lou Ann Kling has teamed up with Bob Smith, a neighboring farmer, to help farmers work out cash-flow statements and farm-spending plans to use in defending their loan cases before FmHA officials. But, she said, the counseling has another effect.

"When they leave here, I see a little bit lighter step," she said. "I try to encourage them not to be afraid of the officials. To treat them as they would treat their own hired hand--which is what the FmHA official is.

"We are not out to 'get' the FmHA. We want to keep people on their land. I've had farmers sit and cry and cry with me, they're so depressed. I tell them they are human beings and this situation isn't their fault necessarily. It's important for them to hear that."

Charles Bellman, undergoing a bankruptcy reorganization on his 5,000-acre spread, said that by the time he and Lois Papousek have gone through a farmer's portfolio and outlined his options, the change in attitude is dramatic.

"You should see the relief on those people's faces," he said. "They come in here bewildered--we've had some ready to commit suicide--but when we give them an idea of their rights and what they can do, it's like waving a magic wand over them.

"We didn't know we had rights as debtors until we started asking questions," Bellman continued. "We felt that no one seemed to know the rights of debtors, and we felt it was up to us or somebody to tell farmers what they can do . . . . This keeps us going, too. By talking to others in trouble, it has helped us."