tween present and projected volume of the sample 
trees was then expressed as a percentage increase and 
applied directly to the inventory volume. 
Drain 
Data on forest industries and estimates of com- 
modity drain for 1940 were based upon an intensive 
field canvass of primary forest-products plants and 
domestic wood consumers. Since 1940 the Forest 
Service has cooperated with the Bureau of the Census, 
and since 1942 also with the War Production Board 
and its successor, the Civilian Production Administra- 
tion, to obtain data on production of lumber and other 
forest products and related wood-products statistics. 
Computations 
Compilation of the inventory and growth data was 
accomplished through the use of punch cards. The 
machine tabulations obtained from the punch cards 
could be used directly in the preparation of the final 
tables. The flexibility, uniformity, and economy of 
this method made possible the rapid, precise compila- 
tion of a large volume of data at reasonable cost. 
Defimtions of Terms Used 
The technical and uncommon terms used in this 
report, as well as certain common terms given spe- 
cial meaning, are defined as follows: 
Land Use Classes 
Commercial forest—Forest land having qualities essential 
to the production of merchantable timber. 
Public reserved forest—Forest land in Federal and State 
ownership upon which commercial timber cutting is pro- 
hibited. 
Noncommercial forest—Forest land too poor in quality to 
produce merchantable timber in a reasonable time. 
Cropland—Nonforest land used for production of farm 
crops within the last 5 years. 
Abandoned cropland—tLand once cultivated, now defi- 
nitely abandoned for farm crops and not being used for pas- 
ture. No forest cover present. 
- Pasture—Cleared, fenced lands that are used primarily 
for grazing. 
Marsh—Low, boggy, nonforested areas bordering water 
' bodies and streams, where drainage is too poor to permit 
agricultural use. 
Other nonforest—Includes areas within the corporate limits 
and suburban or industrial sections of towns and cities; power, 
rail, and highway rights-of-way; sand dunes, beaches, water 
areas, and other miscellaneous nonforest land. 
Forest Types 
Loblolly pine—Stands in which softwoods form 25 percent 
or more of the dominant and codominant trees, with loblolly 
Virginia Forest Resources and Industries 
pine predominating. Includes pond pine in the Coastal 
Plain. 
Shortleaf pine—Stands in which softwoods form 25 per- 
cent or more of the dominant and codominant trees, with 
shortleaf pine predominating. Redcedar is included here, 
although it forms a distinct type over limited areas. 
Virginia pine—Stands in which softwoods form 25 percent 
or more of the dominant and codominant trees, with Virginia 
pine predominating. 
White pine—Stands in which softwoods form 25 percent 
or more of the dominant and codominant trees, with white 
pine predominating. 
Bottom-land hardwoods—Stands of mixed hardwoods in 
swamps and along streams, with hardwood species forming 
75 percent or more of the dominant and codominant trees. 
Includes cypress and white-cedar in the Coastal Plain. 
Cove hardwoods—Stands in which yellow-poplar, cucum- 
bertree, red maple, white ash, river birch, and basswood form 
75 percent or more of the dominant and codominant trees; 
usually found on lower north slopes and in coves along small 
streams. This type includes stands of northern hardwoods, 
with sugar maple, beech, and yellow birch making up 75 per- 
cent or more of the overstory. 
Upland hardwoods—Stands on well-drained, upland sites in 
which mixed oaks and other hardwoods form 75 percent or 
more of the dominant and codominant trees. 
Diameter Classification 
D. b. h. (diameter at breast height)—Diameter in inches, 
outside bark, measured at 4.5 feet above average ground level. 
Diameter class—All trees were recorded in 2-inch diameter 
classes, each class including diameters 1 inch below and 0.9 
inch above the stated midpoint; e. g., trees from 7.0 to and 
including 8.9 inches are placed in the 8-inch class. 
Tree Classes 
Sound saw-timber tree—A softwood tree at least 9 inches 
d. b: h.,; or a hardwood tree at least 13 inches d. b. h., with 
not less than one sound butt log 12 feet long, or with at least 
50 percent of the gross volume of the tree in sound saw timber. 
Sound under-sawlog-size tree—Any straight-boled tree be- 
tween | inch d. b. h. and-sawlog size, sound enough to indicate 
that it could eventually make a sound saw-timber tree as de- 
scribed above. Cord and cubic-foot volumes include trees 
5.0 inches d. b. h. and larger. 
Cull tree—Any tree that fails to qualify as a sound tree 
because of poor form, excessive limbiness, rot, or other defect. 
Pole tree—A pine tree that will produce a pole conforming 
to specifications of the American Standards Association. 
Forest Conditions 
Old-growth timber—Mature or overmature forest growth 
having characteristics of the original mature timber. 
Second-growth timber—Trees that have come up after the 
removal of the old stand by cutting, fire, or other cause, or 
young trees left after logging old timber. 
Saw-timber stands—Stands containing at least 600 board 
feet per acre in pine types, and 1,000 board feet in hardwood 
types. 
Cordwood stands—Stands of trees below sawlog size but 
averaging more than | inch d. b. h. which may contain some 
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