Table 5.4—Ranges of direct costs for three treatment cost levels of management practices to increase net annual 
timber growth in the South 
1985 dollars per acre 
Management practice 
Site preparation for pine on nonstocked land 
Site preparation for pine on cutover pine sites 
Site preparation for pine on cutover hardwood sites 
Plant pine 
Natural regeneration of pine 
Natural regeneration of hardwood 
Precommercial thin 
Hardwood control 
Release seedlings and saplings 
Commercial thin fixed cost 
Treatment cost level 
Low Medium High 
0 20-25 45-85 
20-35 45-85 90-150 
45-85 90-150 110-180 
32-48 40-60 48-72 
24-48 30-50 36-60 
28-56 35-70 42-84 
30-40 40-50 48-60 
32-56 40-70 48-84 
32-40 40-50 48-60 
32-40 40-50 48-60 
Table 5.5—Mean annual increment of growing stock trees for well- 
stocked stands in the South, by forest management type and site 
class for selected stand ages 
Cubic feetiacre/year! 
Forest management Site Stand age 
type? class* 25 35 45 55 
Pine plantations® High Li2-: 102 94 87 
Medium 76 76 73 70 
Low 40 48 50 51 
Natural pine High 97 90 78 67 
Medium 60 61 56 50 
Low 24 31 32 30 
Mixed pine— High 65 63 59 56 
hardwoods Medium 48 48 45 42 
Low 18 23 24 22 
Upland hardwoods High 64 64 59 52 
Medium 4] 45 44 40 
Low 20 27 29 29 
Bottomland hardwoods — High 75 73 67 59 
Medium 49 56 55 49 
Low 38 42 40 3] 
' Mean annual increment includes growing stock trees only. Total 
biomass yield are higher. 
° See text for description of forest types and site classes. 
> Yields for pine plantations reflect average survival and stocking for 
all planted pine types and the use of genetically improved planting 
stock. 
238 
group rather than site-specific yields. Yield tables included 
growing stock volume, percent pine stocking, and percent 
of growing stock volume in sawtimber. 
Economic Assumptions and Analysis—Management op- 
tions were analyzed to determine present net worth and in- 
ternal rate of return. All analyses were conducted in real 
terms, and inflation effects were excluded. No income taxes, 
ad valorem taxes, or land costs were included in the analy- 
ses. A 4-percent real rate of return was used for discount- 
ing all costs and revenues. This 4-percent rate approximates 
the average longrun rate of return to capital in the private 
sector. All management options were projected for long peri- 
ods of time so that treated and untreated cases were compar- 
able. All costs were assumed to remain constant in real 
terms. 
Although 4 percent approximates the average longrun rate 
of return on investments in the private sector of the econ- 
omy, it is an average, and many management options yield 
higher rates of return. Some of the investments in stand 
treatments could yield rates of return in the range of 15 to 
20 percent. In order to provide some measure of the size of 
the economic opportunities to increase net annual timber 
growth with high rates of return, all options were also ana- 
lyzed with a 10-percent rate of return. 
Management options were combined with treatment costs 
and stumpage prices for each production region to construct 
