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The Timber Resource 
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Timber Is a Crop 
When white men began to settle this country 
the timber stand probably amounted to at least 
8,000 billion board feet. ‘This enormous volume 
was very largely in virgin timber, centuries old. 
Now we have about 1,600 billion board feet, only 
about half virgin. In the course of 300 years, and 
chiefly during the last century, we have used or 
destroyed most of our original timber heritage plus 
much of what has grown in the meantime. The 
time is long past when timber could safely be 
viewed as a reserve to be drawn upon without re- 
gard for replacement. It must now be regarded 
as a crop. 
The timber crop must be harvested in trees of 
a size and quality suitable for commercial use;® and 
since about 80 percent of all timber products are 
cut from trees of saw-timber size, it is important to 
think of the timber crop primarily in terms of saw 
timber.* 
To maintain an annual crop of merchantable 
timber, there must be a succession of age classes 
from seedlings up to full-grown timber so that 
as merchantable trees are cut each year new ones 
will be ready to take their places. If the age 
classes were properly balanced and the amount cut 
each year were equal to the annual growth, the 
® Viewing commercial requirements in the broadest sense, 
trees 5 inches in diameter breast high or larger may be 
considered merchantable. Even for fuel wood, distillation 
wood, and other bulk products, it is not profitable to cut 
trees smaller than that. But for lumber the trees must be 
larger. 
7Saw timber refers to trees large enough for sawlogs in 
accordance with practice of the region, regardless of actual 
use. Throughout the East softwood saw timber does not 
commonly include trees under 9 inches in diameter breast 
high. For hardwoods the minimum size varies by species 
and regions but is usually greater than for softwoods. In 
the pine types of the West trees must be 11 inches in diameter 
_ to be called saw timber; in the Douglas-fir types 15 inches 
is the corresponding limit; in redwood, 23 inches. 
Forests and National Prosperity 
volume of standing timber would remain constant. 
It could then be viewed as growing stock or forest 
capital on which the annual crop accrues as in- 
terest. In this light, until the productive capacity 
of the land is reached, the more growing stock or 
standing timber there is, the greater the crop avail- 
able for cutting each year. 
This does not apply strictly to virgin forests, be- 
cause in them death and decay usually offset current 
growth. ‘They do not fully meet the growing-stock 
concept until they have been converted to a net 
growing condition by removal of overmature trees. 
The Timber Stand 
As of the beginning of 1945, the stand of saw 
timber was estimated at 1,601 billion board feet 
(table 4 and fig. 3). ‘The volume of all timber 5 
inches or more in diameter breast high was 470 
billion cubic feet. These are large figures. But 
critical examination shows that growing stock or 
forest capital is by no means satisfactory. 
For one thing, growing stock east of the Great 
Plains is badly,depleted. The land is generally 
understocked. Although three-fourths of the com- 
mercial forest land is in the East, the timber there 
—558 billion board feet—is little more than one- 
third of the national total (fig. 4). Largely second 
growth, it is generally of poorer quality than the 
virgin timber. Saw-timber stands in the North 
average only 3.8 thousand board feet per acre and 
in the South 3.3 thousand. 
On the other hand, two western regions—the Pa- 
cific Northwest and California—with less than one- 
seventh of the commercial forest land, have more 
than half the saw timber in the United States. In 
the Douglas-fir subregion the saw timber averages 
38 thousand board feet per. acre. Such heavy 
stands are also characteristic of the redwood belt 
in California. 
Almost 80 percent of the 1,043 billion board feet 
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