in the Piedmont and mountains is down about 25 percent. 
This decline has just about offset a 20-percent increase in 
the net annual growth of pine in the Coastal Plain. Most 
of the increase in the Coastal Plain can be attributed to the 
development of extensive acreages of pine plantations on 
forest industry land. Net annual growth of pine on forest 
industry land is up more than 50 percent between the two 
most recent surveys. 
To date, resource analysts have identified at least four major 
factors causing the reduction in pine growth (Sheffield and 
others 1985): (1) a continuing decline in area of timberland, 
(2) inadequate pine regeneration on other private land 
following harvesting, (3) a sharp increase in annual 
mortality, and (4) reductions in the rates of tree diameter and 
stand basal-area growth in parts of the region. Although it 
is difficult to quantify how much of the overall reductions 
in volume growth has been caused by each of these factors, 
they all have contributed to the decline in significant ways. 
Decline in Area of Timberland—Past land use changes in 
the Southeast have significantly affected timber growth in 
the region (Boyce and Knight 1980). Major shifts in land 
use since 1945 are particularly relevant to the recent 
reduction in pine timber growth. Between 1945 and 1969, 
the area of cropland harvested in the Southeast dropped by 
more than 10 million acres according to statistics from the 
U.S. Census of Agriculture. Much of the former cropland 
regenerated naturally or was planted to trees, and the area 
of timberland in the region increased by 4.4 million acres. 
During this period, natural seeding and planting of pine 
trees on idle cropland more than compensated for the failure 
to regenerate pine stands after harvests. Today’s age distri- 
bution of pine and mixed pine—hardwood stands on other 
private land in the Southeast reflects the high rate of pine 
establishment between 1945 and 1965. More than 40 percent 
of all pine and mixed pine—hardwood stands on other private 
land are between 20 and 40 years old. 
In the 1960’s the acreage of cropland harvested bottomed 
out, and since 1969 the region has experienced an increase 
in cropland largely caused by a rise in the production of 
soybeans. The area of cropland harvested has increased by 
3.6 million acres. Many acres of timberland have been 
cleared for agriculture. In addition, conversion of timber- 
land to urban uses continues at the rate of 170,000 acres 
annually. The net result has been a 6.1-million-acre 
decrease in area of timberland since 1962. 
Because of this turnabout in cropland acreage, a major 
source of pine regeneration on other private land has dried 
One of the causes of the declining trend in 
net annual softwood growth in the South 
has been the decrease in timberland area 
resulting from the conversion of timberland 
to crop and urban uses. 
up. Since many private owners in the region fail to regen- 
erate their pine stands after harvest, many of the acres 
retained in timberland have reverted to hardwoods. In the 
absence of any large-scale establishment of pine on non- 
forest land, the area of young pine stands on other private 
land dropped rapidly. As a result, there are 30 percent 
Another factor causing the reduction in net 
annual softwood growth in the South is 
inadequate regeneration of pine after timber 
harvests on other private ownerships. Most 
of these owners accept whatever regeneration 
nature provides after harvest. Mixed pine— 
hardwoods or hardwoods naturally replace 
pine stands after harvest over much of the 
South. 
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