Ten years ago, this dusty clearing in the jungle was the heart of a massive government plan to turn northern Amazonia into a South American Iowa -- acre after acre of forest felled to make way for the croplands of Brazilian pioneers.

The colonists would come, government officials declared, from the poorest part of Brazil, the drought-prone plains of the Northeast. To the west and south of "new Brazil," as this first settlement was called, as many as a million peasant farmers, travelling the new Trans-Amazon highway, would build new lives for their families while making it clear to the world that this stretch of Amazonia belonged solely to Brazil.

"Land with no men, for men with no land," was the rallying cry of the era. The printed government plan for Brasil Novo, a large and handsome volume full of diagrams and housing plans, said the colonization would help end social tensions and would "mark out, by the presence of the Brazilian man in Amazonian lands, the conquest of that which has always belonged to him, for him and for his country."

"It's a wonderful piece of work," mused Father Pedro Leo Schneider, the priest whose tiny wood church sits in the heart of Brasil Novo, as he flipped through the pages of the big government prospectus. "If they had carried it out, things would be much better here."

Brasil Novo, the showplace of the last decade's colonization plans, is today a small cluster of wood buildings and burned-away jungle on either side of a highway that some Brazilians have begun calling the "Transamargura" -- Trans-bitterness. Along the length of road that was supposed to draw hundreds of thousands, about 6,000 families now live on government-allocated, low-cost lots, growing products like cacao and sugar cane and living a dozen people at a time in little tin-roofed houses on their plots.

Sixty percent of the original colonists have left, many of them defeated by settlement years far more difficult than anything they had imagined. Of the planned elaborate system of "agrovillas," scattered government communities to provide full services to the farmer, a fraction have actually been completed, and their usefulness is limited -- "there's an agrovilla that they're using for firewood," Schneider said.

Farm prices are low, harvesting methods are primitive, transportation on the Trans-Amazon is expensive, fungi and pests attack the crops, and the government by now has cut way back on what one colonization official here called "an investment that has no return."

"The colonist asks me, 'What can I do?' " said Schneider, who also owns a small parcel of land near Brasil Novo. "The same thing is happening to me. I tried cattle. I tried rice. I tried beans. I don't know what to do. People try. They don't have money. If you take a colonist and turn him upside-down, nothing comes out of his pockets. They eat manioc flour, rice, beans, potatoes -- they eat the production from home . . . . The bank tries to frighten them, and if they get frustrated and desperate and sell their lots, they get nothing for them.

"I've had a colonist, who thinks I'm rich, try to sell me his lot three times. He wants to sell it for 300,000 cruzeiros $2,600 -- a hundred hectares 247 acres -- to pay off a debt of 50,000 cruzeiros $450 in the bank."

From Brazil Novo down through eastern and southern Amazonia, 15 years of scattered colonization efforts have taught the Brazilian government that their grand-scale project -- putting 20th-century pioneers from a Third World economy onto tropical forest soils -- was a lot more complicated than they thought.

In Rondonia territory, where the soils are good, pioneer families are pouring in so fast that the colonization agency cannot keep up with their demands for land. In southeastern Para State, where cattle ranchers and Brazilian agribusiness have bought in en masse, colonist families are nearly at war with large landowners trying to move them out -- houses are burned down, both sides pack loaded pistols, and a local lawyer said this month that conflicts in one especially bitter Para area have killed four people so far.

Around Brasil Novo, the Northeastern poor began arriving 10 years ago, when government spread the word about the fine future that awaited them in Amazonia. But many of them were so poor and so accustomed to the traditional simplicity of Northeastern farming that ill-prepared colonization officials could not or would not give them the support they needed -- transportation, the right kinds of seeds, medical care for the malaria and tuberculosis that swept through the settlements, a storage and sales system to help them market their crops.

The rice that had grown well in hot dry Northeastern states never made it to full harvest in the hot, wet Amazon. Twenty kinds of sugar were planted, and failed, before agronomists came up with something promising. "We have now a lot of experience from the early days," said Carlos Ribeiro, colonization director for the National Institute for Colonization and Agrarian Reform (INCRA), which now says it has 200,000 families living in low-cost, low-interest lots all over Brazil. "Unfortunately, we had to learn with the suffering of so many people."

"They told us people would be living well here, like in the city," said Maria Jose de Medeiras Costa, a broad-backed older woman from the Northeast who has stuck it out with 11 children in a tin-roofed Brasil Novo house ever since government people came to her part of the Northeast 10 years ago to recruit pioneers.

"They said we were going to have water, schools, electric light. We got here and there was nothing, just this house. To go to the city you had to get up at two in the morning, walk 14 miles, and catch a truck . . . and the piunes -- the little mosquitos -- you can still see the scars on my arms now. Some children died from the bites."

"Some of them were afraid of the jungle," Schneider said. "They came from a region where there is no forest, where you had to walk five kilometers to find a piece of wood. The rains were terrible, and the piunes were a torment. They suck blood, and they transmit a disease that was then called" -- named after the city 30 miles away -- "Altamira yellow fever. People would scrape the piunes off the screens and fill a shoebox full of them."

And there were those who arrived thinking of themselves as laborers, Schneider said. "We went to a meeting and explained that this wasn't INCRA's land, that it was supposed to belong to them, that it wasn't a big estate. For them a hundred hectares 247 acres was a big estate. They were used to five or six hectares. And they'd say, 'No, I don't want it. I don't want to own this land.' There was a paternalism on INCRA's part, and people who were ready to take advantage of it."

As though those were not troubles enough for a vision of "land with no men for men with no land," scientists over the years have discovered the crashing irony of jungle soils. This enormous forest, with a plant life so profuse that experts studying it have counted 3,500 different usable lumber trees, grows out of some of the worst soil on the face of the earth.

Spread over what was once the bottom of a massive freshwater lake, the soils that cover much of Amazonia have for millions of years been leeched of almost every nutrient that makes plants grow. "It is exactly the contrary of our Atlantic forest, where we have 90 percent of our nutrients in the soil and 10 percent in the forest," said Henrique Bergamin, the Brazilian chemist who directs the National Institute for Amazon Research in Manaus. "Here you have 90 percent of the nutrients in the forest and 10 percent in the soil."

One of nature's more elegant adaptation systems is at work in the rain forest that grows so abundantly from Amazonia's infertile soils. As you stand on the forest floor and look up -- at the will roots that twist out and barely dig into the ground, at the fungi that cling to the bark of trees, at the orchids and lilies and winding liana vines -- the rain forest's nutrients are right before your eyes.

With every rainstorm, every shaft of sunlight, every fallen leaf or branch or tree, the forest takes what it needs so directly and efficiently that the soil is mostly bypassed. Plants grow almost straight off the sun and rain. Vegetation rots into the shallowest top layer of the earth and then quickly feeds the growing trees around it.

A farmer who clears this forest in the traditional way -- chopping down what he can, and then burning the ground cover -- will find that after one year his plants are thriving as they feed off the nutrients released in the ashes. After the second year, they are drooping pretty badly. After the third year, they are withered almost beyond use, and the farmer has to chop and burn a whole new patch of forest to start planting again.

Not all of Amazonia consists of such terrible soils. "There are plots and plots," Ribeiro said as he sat in his 16th-floor, air-conditioned office in Brasilia. "There are good soils, bad soils, poor soil, rich soil, good climate, bad climate, plant disease, regions without any plant disease."

Some Amazon pioneers, especially the new breed of more sophisticated and technically knowledgeable farmers who have moved up in recent years from the developed farmlands of southeastern Brazil, have been able to make their lands produce. "Look -- I had nothing -- I came with nothing," said Jose Morais Filho, the thin and weathered Northeastern patriarch of a 60-head cattle farm that sits in the thick red dust alongside the Trans-Amazon highway.

Morais' house is simple and crowded, with glassless windows and a bare light bulb hanging in the main room, but he invited his visitors in for platefuls of cheese and thick caramel sauce made from his cows' milk. "I came with a wife, 12 children, and one grandchild," Morais said. "The capital we brought was 270 cruzeiros" -- then about about $48. "Now what I have here I wouldn't take 10 million cruzeiros for."

But failing some massive fertilization program that most people now think too costly and complicated to be practical, Amazonia is clearly not the potential breadbasket and promising homesteaders' territory that some Brazilian officials imagined as recently as 10 years ago. In the mid-1970's, the government openly shifted its attention away from colonization projects, and instead began encouraging large cattle ranches by offering good financing and tax incentives.

"We have very modest goals," said INCRA President Paulo Yokuta, sounding quite different from the ambitious declarations of the last decade. "The intention is not to occupy all the Amazon . . . . I think if you have regular agriculture or livestock activity in the Amazon, I think you're going to talk about 10 percent in one century."

That has not stopped colonists from coming, but it has sharply cut back the amount of government money available to help them obtain land and get underway. People in Brasilia no longer talk the same way about "land with no men." There is still plenty of land with no men in Amazonia, but scientists, agronomists, sociologists, and government planners are still arguing about how to use it without fueling more pioneer-rancher battles or making permanent war on the delicate ecology of the world's largest rain forest.