Pine from 12 western states is the single biggest source of timber in the United States - 9.9 billion board-feet last year. Douglas fir from western Washington and western Oregon provided another 8 billion board feet in 1976.

Southern states produced 7.9 billion, and these regions combined accounted for more than half of the nation's timber production.

Unlike the South, where individuals own most of the woodlands, the western states are heavily dependent - about 50 per cent - on federally owned lands for their supplies. Thus higher prices go more to the U.S. Treasury and less to the local economy.

All told, the United States consumed some 43 billion board feet of wood last year, with 20 per cent of that imported, primarily from Canada. One-half of the total went for lumber and plywood, with half of that used in new home construction. (One-fourth of all paper is made from sawdust and leftover wood chips of this production).

In 1973, when the last sharp rise in prices occurred, there were 2.5 million new housing starts. The federal government says the current pace of new housing construction is about 2 million for 1977.

Demand for single-family houses has increased the most, a type of construction that requires some 50 per cent more lumber and plywood per unit than multi-family housing.

Between the high-price years of 1973 and 1977, housing starts plunged, as did prices for wood products.

Joe Muench, and economist with the National Forest Products Association, says that while the cost of buying trees has gone up 462 per cent since 1970, the average price of finished building materials at the mill has risen only 143 per cent. He says that increased efficiency and new technology have allowed the industry to absorb some of the increase in timber prices.