fewer pine and mixed pine—hardwood stands 20 years old 
and younger than similar stands between 20 and 40 years 
old. 
Based on the 1982 statistics from the Census of Agriculture, 
the increase in area of cropland harvested in the Southeast 
has almost halted; however, timberland is still being rapidly 
diverted to urban and related uses. The pine and mixed 
pine—hardwood types experienced a 2.7-million-acre net 
decrease between 1977 and 1985. Most of the decline has 
been on other private land. 
Inadequate Regeneration on Other Private Lands— 
Another factor causing the reduction in net annual pine 
growth is inadequate regeneration on other private land 
after harvesting. While recent forest surveys show some 
improvement in the regeneration on such land, the record 
during the 1960’s and 1970’s was not good. Many private 
owners accept whatever regeneration nature provides after 
timber harvests. In many cases, hardwoods or mixed stands 
of pine and hardwood replace pine without some interven- 
tion on the part of the landowner. Changes on other private 
land are especially important because these owners account 
for about two-thirds of the timberland in the Southeast. 
Over the past 10 years, the area of other private land 
harvested and kept in timber has averaged about 950,000 
acres each year. This figure includes both final harvesting 
and high grading but excludes thinning and other inter- 
mediate cutting. Of these 950,000 acres harvested, 610,000 
acres supported pine or mixed pine—hardwood stands prior 
to harvest. On other private land, the total area successfully 
regenerated to pine or mixed pine—hardwood averaged about 
330,000 acres, or less than 55 percent of the pine and mixed 
pine-hardwood acreage harvested. Over the same 10-year 
period, area regenerated by planting to pine averaged less 
than 20 percent of the acreage of pine and mixed pine— 
hardwood harvested. 
Planting statistics indicate the annual rate of planting on 
other private land has increased significantly in recent 
years. Planting on other private land occurred on approxi- 
mately 400,000 acres in 1984 and 500,000 acres in 1985. 
Still, the rate of planting is much below that of harvesting. 
About 1970, the consequences of inadequate pine regenera- 
tion on other private land and the absence of widespread 
pine seeding onto idle cropland began to show up in the 
forest survey statistics as reductions in numbers of pine 
saplings. The latest cycle of surveys shows 40- to 50- 
percent declines in the numbers of pine saplings on other 
private land. More important, these declines in tree numbers 
150 
have now progressed up into the 6- and 8-inch diameter 
classes, where they are affecting ingrowth and inventory 
volumes (fig. 3.25). Since some of the sharp decrease in 
numbers of pines can be attributed to the shift from dense 
natural stands to plantations, prospective declines in the 
larger diameter classes are somewhat smaller than those 
anticipated in saplings. A 60-percent increase in the number 
of 6-inch pines on industry land over the past 10 years only 
partially compensated for the loss of 6-inch pines on other 
private land. 
Increase in Annual Mortality—A third factor affecting the 
reduction in net growth is a sharp increase in the mortality 
of timber. Pines have experienced the largest increase in 
mortality. Statistics indicate 15 percent of the gross annual 
growth of southern pine is now lost to mortality, compared 
to 9 percent 10 years ago. In timber volume, the annual 
mortality of pine has increased about 80 percent over the 
past decade (table 3.17). 
Much of the increase in mortality can be attributed to 
periodic outbreaks of pine bark beetles over fairly extensive 
areas. Forest survey statistics suggest that insects account 
for 35 to 40 percent of the softwood mortality in the 
Southeast each year. Suppression is the second leading 
identifiable cause of death, followed closely by disease. 
Fusiform rust, littleleaf disease, and annosus root rot are the 
three leading diseases affecting pines in the region. 
Reductions in Growth Rates—A fourth factor affecting 
the slowdown in growth is measured reductions in the rates 
of tree diameter and stand basal-area growth for natural 
pines in parts of the region. To date, forest survey has 
measured significant declines in the Piedmont and moun- 
tains of Georgia, South Carolina, North Carolina, and 
Virginia. In these regions, average annual radial increments 
of pines determined from remeasurements of sample trees 
at breast height have averaged some 20 to 30 percent lower 
over the past 10 years than over the previous 10. 
A reexamination of older forest survey data on rates of tree 
growth indicates the decline extends back even further than 
the past 10 years and also shows up in parts of the Coastal 
Plain in earlier remeasurement periods. The slowdown in 
diameter growth at breast height on individual trees was not 
detected earlier because it was more than offset by increases 
in stocking and stand age. It is conceded that a slowdown 
in the average rate of growth of individual trees at d.b.h., 
by diameter class, is not conclusive evidence of an overall 
slowdown in softwood growth. Further study, however, 
shows a slowdown in average stand growth expressed in 
