The forests were this country's first depleted resource.

At the turn of the century, conservationists were aroused by the deforestation of vast parts of the country by timber companies. In response to this outery, Congress set aside a reserve of federally protected timber and created the Forest Service.

Today, in parts of the Pacific Northwest the supply of timber on commercial lands is again declining rapidly. The result is strong pressure from many quarters to accelerate the rate at which trees are taken from the national forests - the country's federally controlled tree "bank."

The pressure is coming partly from the "multipulps" - the huge international paper and timber companies.

But Barry Bosworth, director of the president's Council on Wage and Price Stability, has also suggested that Secretary of Agriculture Bob Bergland could direct the Forest Service to put more federal timber up for sale to combat inflation in lumber prices, which in turn, pushes up the cost of housing.

John Beuter, head of the department of forest management at Oregon State University, fears that if present practices and policies continue in the Northwest, there will be mill closings and unemployment in years to come. The combination of heavy cutting by the multipulps on commercial lands and restrictive tree-harvest policies of the Forest Service could mean a 22 percent decline in the annual harvest in western Oregon by the year 2000, Beuter predicts. That would mean a loss of jobs and economic activity.

However, proposals to increase the cutting of trees in national forests for the sake of jobs, communities and lower lumber prices have been sharply criticized by environmental organizations. Douglas Scott of the Sierra Club calls Bosworth's proposal "egregious nonsense." Scott notes that lumber cost is only a minor portion - usually no more than 17 percent - of the overall price of a house. If the government wants to depress the cost of building homes, it should take action to lower labor expenses and mortgage interest rates, he insists.

For environmentalists, the issue is especially emotional because any significant increase in the volume of wood coming out of the federal forests would have to come from some of the most beautiful trees in America: the 200- to 300-year "old-growth" stands of Douglas fir and hemlock west of the Cascade Mountains in Oregon and Washington. Oregon alone supplies about one-quarter of the wood now being taken from national forests. Washington, California, Idaho and Montana supply another quarter.

"We are at the turning point, no question about it," says Beuter in reference to the forests of the Pacific Northwest. "There is the realization that we have all this milling capacity but may not have the timber to support it. There just isn't that much timber left on commercial lands."

The choices between conservation and economic necessity have become familiar to Americans in the last decade. The world needs more food; but water tables in western Kansas are declining because of crop irrigation. The country needs more energy; but extracting oil from the shale in Colorado and Wyoming poses the threat of air pollution and environmental damage.

In the case of the national forests, the situation may not yet be so serious. Forests, unlike water or oil, can be restored and replenished. States such as Washington now require all harvested acreage to be replanted or resown with trees within a year. In the long run, with adequate laws, supervision and management, there is no doubt that the nation can produce an adequate amount of timber.

However, experts in industry and government concede that parts of the nation are now entering a period of "timber gap," during which pressure on available timber resources will be extreme until seedlings and plants mature well after the turn of the century.

This gap, which is most severe in the Pacific Northwest, grows out of the accelerated cutting by multipulps such as Weyerhaeuser, Georgia-Pacific, Louisiana-Pacific and others. In the 1960s, all the companies accelerated their logging operations, converted more trees into logs, lumber and paper, and used the income to diversify, expand and extend their land-holdings in the United States and abroad.

For this reason, the timber companies have become targets of criticism in the Northwest. The export to Japan of logs cut from trees in Washington and Oregon has become a contentious issue in those states.

However, as the companies point out, the heavy cutting has served a real need - the requirement of American and Japanese for wood to build homes. Rising lumber prices in recent months suggest that the need for construction wood is greater than ever.

As the demand for timber has increased, so has the pressure on the Forest Service to allow more cutting of trees on federal lands.

Only about 96 million of the 500 million acres of harvestable timberland in the United States presently are in the national forests. But this figure is somewhat misleading. The national forests contain about half the nation's supply of softwood - the pine, fir, spruce and hemlock that is the choice wood for making lumber and paper.

And in fiscal 1977, the Forest Service auctioned off 10.5 billion board feet of trees to private industry - about one-sixth of all the wood cut in the country for lumber, paper manufacturing and furniture.

Some say this cutting on federal lands is much too cautious, especially in the Pacific Northwest.

"There are compelling facts to demonstrate that the Forest Service is overconservative," says Luke Popovich of the Journal of Forestry.

Popovich gets some support for this position in a report issued in October by the Council on wage and Price Stability. The report stated that the harvest from federal timber lands rose by 236 percent between 1950 and 1969 but that the harvest declined by 37 percent between 1969 and 1976 - a period when demand for timber (and the price of lumber) was rising rapidly.

"An examination of future demographic trends together with expectations of a decline in the inventory of timber on private lands points to a continuing threat of higher lumber prices into the mid 1980s," the report said. It added that future demand cannot be met by the supply of wood available under current forest management policies, and concluded that "alternatives" to present policies should be considered.

According to the council's Thomas M. Lenard, an average American home would be $3,563 cheaper today if lumber prices had not risen since 1974. But environmentalists say that many factors besides the price of the trees affect lumber prices - the energy costs of running sawmills and transportation, to name two.

Those opposed to a faster cutting rate in the federal forests of the Northwest have a friend in Sen. Herman E. Talmadge (D-Ga.), chairman of the Senate Agriculture Committee.

In 1976, Congress enacted a national forest management law that took a fairly conservative position on cutting practices. It upheld the principle that the national forests must serve all people, not just commercial timber interests, by providing recreation facilities and wilderness, and by preserving the aesthetic features of the woodlands.

The conservative approach was favored by Talmadge. Congressional sources say one reason was that he feared that if large amounts of wood from the federal forests of the Pacific Northwest were dumped on the market, the wood from thousands of private holdings in the South would lose its competitive edge in the big lumber markets on the eastern seaboard.

The 1976 act says that the Forest Service must schedule the cutting of trees on its land in such a way that as much or more wood can be harvested year after year. This equates the tree cutting with reforestation, since they Forest Service could not meet this formula if it did not develop new growth on its land.

Environmentalists say this was meant to prevent the rapid depletion of the high yield, "old-growth" trees. The old growth can be cut - but only over a long period if the nondeclining harvest formula is to be observed.

But the act does give the secretary of agriculture leeway to depart from the strict interpretation "to meet overall multiple-use" objections.

Government studies are now under way on whether the situation in the Northwest justifies faster cutting. Scott says the Sierra Club has a lawsuit ready if the government attempts to speed the cutting of the "old growth."

In 1974, a suit by the National Resources Defense Council prevented the Nixon administration from increasing the harvest on federal lands by 1 million board feet.

"The message on that suit was that you just don't go chopping down the national forests," says Scott.

He says the government should be looking for ways to get more timber out of the woods and into the market from other sources, such as privately owned lands. Some have suggested government incentives to encourage this.

"This is the harder way of doing," Scott says. "But it does not have the tremendous impact on the environment. They're [in Washington] looking at this problem like economists, not biologists."

What the biologists say is that new generation of big old-growth timber will not replace it in time for our great grandchildren to see it.