and hardwood for clearcui” aak-hickory iype by year of harvesi and basai area ciass, Louisiana, 1975-1991

Basal area class (Square feet per acre) _

<20 20-39 40-59 60-79 30-99 2100
Year of, All, ve = ry = =e
harvest nt SE! hard’ Soft! Hard” Soft! Hard” Soft! Hard” Soft! Hard” Sofi! Hard Soft! Hard
Cubic feet per acre. ---- +--+ +-+2 +2222 2 eee tee eee n ee eee eee eee
1975 2 0.2724 1,403.3 0.5219 559.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1403.3 559.4
1976 1 0.0000 183.7 0.0000 817.5 00 00 00 00 183.7 00 00 00 00
1977 2 00083 1,724.5 0.7101 SLL 00 00 00 00 00 00 00 1745 S14
1978 4 0.3202 894.4 0.4653 212.8 0.0 0.0 0.0 0.0 410.8 0.0 0.0 1378.8 132.3
1979 3 0.3558 00 46900 7109 1428 603.3. 1,387.8
1980 4 0.2082 00 00 00 00 00 922.7 186.6 1,469.8 17.7
1981 4 0.3500 0.0 00 281.2 133.6 485.8 0.0 0.0 0.0 0.0
1982 8 0.2587 00 00 00 00 3426 390.7 1,626.0 00 00
1983 0 0000 00 06 «06 0G HG 00 00 «= 000
1984 4 0.5360 278.6 0 5893 789.6 0.0 0.0 0.0 0.0 636.0 0.0 0.0 358.2 1,729.2
1985 8 0.5374 407.6 0.3600 159.6 50 0.0 185.5 1239 340.0 00 =—0.0 1,9013 220.1
1986 3 0.5515 79.7 1,0000 T21 82.0 0.0 75.3 212.7 0.0 0.0 0.0 0.0 0.0
1987 9 0.7164 142.8 0.3664 113.7 15.5 17.0 95.5 241.7 828.5 0.0 0.0 0.0 0.0
1988 8 0.6061 84.6 0.5062 386.0 78.7 134.8 0.0 0.0 143.0 0.0 0.0 0.0 0.0
1989 5 0.8226 84.80.5353 527.1 2231288 = 0.00.0 170.7 00 00 00 00
1990 9 0.5183 309 03412 5153 23.5948 64.4 500500 00 00 00 00
1991 5 0.7279 60.7 0.4890 187.8 81.2 478 34.6 365.5 0.0 0.0 0.0 0.0 0.0
Allyears 790.1572 367.9 0.1546 383.7 44.2 72.7 123.8 248.0 337.3, 610.7 922.3 1,249.1 5958
sel 0.1572 0.1546 0.4260 0.2829 0.2366 0.2011 0.2119 0.3376 0.5554 0.1364 0.4068
at 9 19 26 26 12 12 18 18 8 8 4 4 ul i

“Clearcut includes seed tree-shelterwood cuts, merchantable clearcuts, and all-tree clearcuts.

Most recent has

Number of sample plots in columns and rows.
{Sampling errors (one standard error) for column and row averages (on a relativized scale ranging from 0.0000 to 1.0000).

‘Softwood species.
"Hardwood species.


Table 9.—A,rea of clearcut loblolly-shortleaf pine forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type
Year of, All Longleaf-slash _ Loblolly-shortleaf_ Bottomland
harvest" nt set types pine. Pine Oak-pine Oak-hickory hardwoods + Nontyped!
aoe cen eee e econ n enna nneneneel Thousand acres ~~~ +++ + +22 0- 22 22eeee eee

1975 10,0000 67 0.0 67 0.0 0.0 0.0 0.0
1976 10 0.3129 58.1 0.0 472 10.9 0.0 0.0 0.0
1977 IL 0.2966 64.6 0.0 52.8 58 6.1 0.0 0.0
1978 11 03146 57.5 0.0 46.2 5.2 6.1 0.0 0.0
1979 12 02854 69.8, 6.2 47.1 4 51 0.0 0.0
1980 110.3108 58.9 0.0 58.9 0.0 0.0 0.0 0.0
1981 12 0.2894 «67.9 6.2 44.3 11.9 5.5 0.0 0.0
1982 17 0.2380 100.1 0.0 94.6 5.6 0.0 0.0 0.0
1983 5 0.4438 (28.9 0.0 15.9 5.5 15 0.0 0.0
1984 3 0.5923 16.3 0.0 1Lt 5.2 0.0 0.0 0.0
1985 4 0.4759 25.2 0.0 25.2 0.0 0.0 0.0 0.0
1986 150.2610 83.4 0.0 45.2 20.2 18.0 0.0 0.0
1987 18 0.2391. 99.2 0.0 425 28.6 28.2 0.0 0.0
1988 21 0.2175 119.7 0.0 46.2 28,3 45.2 0.0 0.0
1989 16 0.2515 89.7 0.0 23.2 34.4 32.1 0.0 0.0
1990 25 0.1953 148.2 0.0 30.6 12.8 104.8 0.0 0.0
1991 9 0.3403 49.2 0.0 59 0.0 43.3 0.0 0.0

All years 201 0.0678 1,143,3 124 643.5 185.7 301.7 0.0 0.0

se! 0.0678 0.6772 0.0920 0.1742 0.1361 0.0000 0.0000

at 201 2 113 33 53 ° 0)

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest.

4+Number of sample plots in columns and rows.

SSampling errors (one standard errot) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘Stands with 0.0 percent stocking; i.e., no live trees in sample.

Table 10.—Area of clearcut oak-pine forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type
Year of, All Longleaf-slash — Loblolly-shortleaf_ Bottomland

harvest at sei types pine pine Oak-pine Oak-hickory hardwoods Nontyped!

voc cne eee ee sees eens sneer erees Thousand acres- ~~ ~~ =--+-2-- 2-2 20e eee ee eee en eee
1975 © 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1976 2 0.7329 10.6 0.0 5.5 5.1 0.0 0.0 0.0
1977 7 03788 =—39.7 0.0 28.3 0.0 14 0.0 0.0
1978 7 0.3808 = 39.3 0.0 11.2 222 58 0.0 0.0
1979 2 0.7314 10,7 0.0 10.7 0.0 0.0 0.0 0.0
1980 7 0.3844 38.6 0.0 26.4 12.1 0.0 0.0 0.0
1981 6 04058 34.6 0.0 16.1 6.2 67 5.6 0.0
1982 5 04197 32.4 0.0 13.0 0.0 19.4 0.0 0.0
1983 3 0.5921 16.3 5.5 52 5.6 0.0 0.0 0.0
1984 3 05908 = 16.3 0.0 16.3 0.0 0.0 0.0 0.0
1985 3 0.6039 15.6 0.0 15.6 0.0 0.0 0.0 0.0
1986 7 0.3794 39.6 0.0 17 0.0 224 54 0.0
1987 8 03511 46.2 0.0 112 29.8 5.2 0.0 00
1988 9 0.3342 «51.0 0.0 163 57 23.0 6.1 0.0
1989 13 0.2815 TT 0.0 16.9 20.9 28.3 5.5 0.0
1990 13 0.2795 727 0.0 114 221 33.5 5.6 0.0
1991 6 04116 33.6 0.0 55 54 22.7 0.0 0.0
All years 101 0.0982 568.8 5.5 2S 135.1 178.4 28.2 0.0
set 0.0982 0,0000 0.1593 0.2046 0.1778 0.4496 0.0000
a? 101 1 40 24 31 5 0)

“Numbers in columns and rows may not total due to rounding.
‘Most recent harvest.
Number of sample plots in columns and rows.
Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘stands with 0.0 percent stocking; i.e., no live trees in sample.


Table 23.—Current volume of softwood and hardwood for clearcut” oak-hickory type by year of harvest and diameter class, Louisiana, 1975-1991"
Diameter class
1.0-2.9 3.049 5.0-6.9 7.0-8.9 9.0-10.9 11.0-12.9 213.0

Year of, All All
harvest?

hardt Soft” Hard’? Soft’” Hard’ Soft”” Hard" Soft” Hard" Soft”” Hard’? Soft” _Hard't Soft” Hara"?
Cubic feet per acre ~~~ === == += 2-22 0220c eee ence eect eee ce eet ee ee ne eee e eens

5
ge
m
$
&.
2
isa

1975 2 0.2724 1,403.3 0.5219 559.4 0.0 164.5 0.0 158.8 160.2 30.0 470.8 0.0 618.3 396 122.8 = 166.6 31 0.0

1976 1 0.0000 =: 183.7 0.0000 817.5 0.0 74 0.0 0.0 0.0 33.0 61.8 = 181.4 0.0 201.3 0.0 80.7 121.8 313.8
1977 2 0.0083 1,724.5 0.7101 St 155.9 265 383.9 0.0 462.9 24.6 470.8 0.0 212.6 0.0 0.0 0.0 38.2 0.0
1978 4 0.3202 «894.4 0.4653 212.8 63.9 83.5 2728 17.2 241.8 0.0 196.8 0.0 86.2 0.0 117 15.2 213 96.9
1979 3 0.3558 «= 654.5 0.7095 1,007.3. 28.1 «159.2 104.9 41.9 84.7 39.6 304.1 55.4 56.9 69.4 00 676 758 574.3
1980 4 0.2052 1,020.8 0.4202 272.5 19.9 117.5 233.6 = 20.7 224.9 10.7 217.0 0.0 69.2 0.0 © §©50.0 196 206.2 103.9
1981 4 0.3500 445.6 04655 242.5 46.4 156.0 136.1 59.9 65.0 20.0 28.5 6.5 18.3 0.0 0.0 0.0 151.4 0.0
1982 8 0.2587 390.6 «0.3952, 627.7 40.0 137.3 69.8 598 152.3 55.2 22.8 22.6 0.0 83.3 96 715 9.0 191.8
1983 oO 0.0000 0.0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1984 4 0.5360 278.6 0.5893 789.6 71.0 106.7 109.3 94.7 14 61.0 29 85.8 13.7 104.8 244 92.9 27.0 243.9
1985 8 0.5374 407.6 0.3600 159.6 126.6 459 243.3 9.0 67 8.1 44 0.0 0.0 19.5 0.0 42.9 26.6 34.2
1986 3 0551S 79.7 1.0000 72.1 645 35.3 00 19.9 0.0 0.0 00 16.9 15.2 0.0 0.0 00 0.0 0.0
1987 9 0.7164 142.8 0.3664 113.7 66 131 236 138 313 45° 287 208 = 33.4 14 0.0 0.0 92 54.1
1988 80,6061 84.6 0.5062 386.0 00 211 0.0 = 18.8 0.0 14.5 67 224 283 808 15.7 478 33.9 180.5
1989 5 0.8226 «= 84.8 0.5353 527.1 00 = 80.8 00 184 =129 42.7 0.0 70.2 0.0 0.0 00 306 718 284.3
1990 9 0.5183 30.9 03412 515.3 94 36.3 0.0 93.4 0.0 33.5 6.7 THA 148 61.1 0.0 26 0.0 141.2
191 5 0.7279 60.7 04890 187.8 0.0 20.8 0.0 0.0 0.0 64.5 15.2 48.0 0.0 13.0 0.0 19.8 45.4 21.6

Allyears 790.1572, 367.9 0.1546 383.7, 37.0 70.1 84.9 39.7 67-40 27.3 0.7 328 45.5 39.0010 44 SS 130.7
sE! 0.1572 0.1546 0.2515 0.1510 0.2410 0.2122 0.2185 0.2501 0.2959 0.2084 0.3580 0.2812 0.3627 0.2287 0.3357 0.2573

“Clearcut includes seed tree-shelterwood cuts, merchantable clearcuts, and all-tree clearcuts.
‘Numbers in rows may not total due to rounding.

‘Most recent harvest.
SNumber of sample plots in rows.

{sampling errors (one standard error) for column averages and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
“Softwood species.
‘Hardwood species.


of 6,888,000 acres across both survey periods for analysis in
the study.

Most harvesting activity (4,01 1,600 acres) was by partial
harvesting (table 1). Clearcutting totaled 2,562,000 acres.
Salvage and seed tree harvests were a minor component of
harvested stands, less than 5 percent of all harvested acre-
age. Heaviest cutting (all types of harvesting) in the 1991
survey period was in 1988 and 1989; 1990 had the highest
amount ofclearcut harvesting, with a total of 311,600 acres.

There were 2,581,100 acres harvested on forest industry
timberland (table 2). Approximately one-half of the har-
vests were partial cuts and one-half were clearcuts. A major
proportion of harvest disturbance has been recent, 1987
through 1990 (1,226,400 acres).

Even more acreage was harvested on nonindustrial pri-
vate forest (NIPF) lands (table 3). Here, 3,852,600 acres
were cut, 2,466,800 acres by partial harvest and 1,205,600
acres by clearcut. Even though more total harvesting was
done on NIPF lands than forest industry timberlands,
equivalent amounts of timberland were clearcut, 1,205,600
and 1,246,100 acres, respectively. Heaviest harvest activity
on NIPF lands was recent, 1987 through 1990 (2,035,100
acres).

Stocking was analyzed by both basal area and the survey
stocking standard. There was substantial harvested timber-
land acreage (2,873,600 acres) with < 60 ft? of basal area
per acre (as of the 1991 survey) (table 4). The table may be
used to demonstrate total stand basal area recovery of
harvested stands over time. There were substantial
amounts of acreage, in stands harvested after 1985, with
< 20 ft? of basal area per acre. In contrast, very few
stands had < 20 ft? of basal area per acre 5 to 6 years after
harvest; i.e., harvested before 1986. This may reflect the
amount of time it takes a tree to reach 1.0 inch in d.b.h.
(because only trees 2 1.0 inch in d.b.h. are used in the
computation of basal area). Stands with more than 100 ft?
of basal area per acre occupied 1,457,600 acres of timber-
land.

The survey stocking classes show only 329,900 acres
with total tree stocking < 60 percent (table 5). This is much
improved in contrast to the basal area classes. The primary
reason for this is that seedlings are included in the assign-
ment of stocking percent but are not included in the basal
area assignment. Most of the very low-stocked stands were
harvested after 1988 and had not fully recovered (either by
planting or natural regeneration) at the time the survey
was done.

Excluding hardwoods from the analysis substantially
increases the amount of timberland in understocked
stands. There are currently 1,289,000 acres of harvested
timberland with < 60 percent stocking in softwoods. Most
of these stands (905,800 acres) were naturally regenerated
after harvest (table 6). However, 383,200 acres were in
plantations (table 7).

Surprisingly, timberland stands that were harvested
more than 6 years ago had 315,500 acres that were < 60

percent stocked with softwoods. Most of these stands were
naturally regenerated (224,700 acres). Approximately 22
percent of the plantations established on these harvested
sites were also < 60 percent stocked in softwoods, as were
30 percent of the stands that regenerated naturally. One
would expect regenerating stands to approach full stocking
as they age, even if initial stocking at the time of a stand
establishment was low. In this instance, there may have
been seedling failure or the time interval between harvest
and stand establishment could have been extremely long
(> 5 years).

Tables 8 through 11 characterize clearcut longleaf
slash pine, loblolly-shortleaf pine, oak—-pine, and oak—
hickory forest types by their respective forest type as of the
1991 survey. These tables imply relative pine stocking
(based on the stocking standard) because forest type is
based on the dominant species. By tracking forest type
from prior-to-harvest up to the current survey, some ef-
fects of harvesting disturbance can be analyzed over time.
Of the 284,300 acres of clearcut longleaf-slash pine, only
118,700 acres have remained in this type (table 8). In the
loblolly-shortleaf pine type, 1,143,300 acres were har-
vested and 643,500 acres have remained in this type (table
9). The oak-pine type had 568,800 acres clearcut (table
10). Currently, 135,100 acres remain in this type, but
221,500 acres have converted to the loblolly-shortleaf pine
type. This represents a notable improvement in relative
pine plurality. There were 458,300 acres clearcut in the
oak-hickory type; the 1991 survey showed 127,200 acres
remaining in this type (table 11). However, much of this
timberland has converted to the loblolly-shortleaf pine
type (186,700 acres), indicating a notable increase in rela-
tive stand plurality of pine.

There is one thing that stands out in these forest-type
tables (tables 8 through 11). Very little of the acreage that
was harvested between 1975 and 1986 is currently in the
oak-hickory forest type, whereas recently harvested stands
(1987 to 1991) have higher proportions in the oak-hickory
type (fig. 1). This may be attributed to heavy sprouting of
hardwoods after harvest and prior to adequate softwood
establishment. Hardwoods are often more dominant (in
height) than pines at this stage of stand development. Since
the survey sample selects the four most dominant seedlings
at each satellite point, typing of some stands in the early
years after harvest will reflect a hardwood type. Of all
upland timberland clearcut since 1975, a total of 640,500
acres is currently in the oak~hickory forest type.

Tables 12 through 15 characterize partially harvested
timberland by current forest types for longieaf-siash pine,
loblolly-shortleaf pine, oak-pine, and oak-hickory forest
types. Most of these partially cut forest types have re-
mained in their former type, but some types did show
significant conversions. Most notable were the 516,000
acres of loblolly-shortleaf pine type, which reverted to the
oak-pine, oak-hickory, and bottomland hardwood types
after harvest. The oak—pine type had 180,600 acres that



Table 20.—Current density of softwood and hardwood for clearcut” pine types" by year of harvest and diameter class, Louisiana, 1975-1991*

Diameter class
10-29 3.0-4.9 5.0-6.9 70-89 9.0-10.9 11.0-129 213.0
Year of, . AML «AWC —— —
harvest’ at __ soft"? SE. hard'* Soft't Hard¥# Soft'! Hard Soft't  Hard** Soft’ Hard** Soft!’ Hara’* Soft"? Hard** Soft’? Hara**
+ -Number of trees per acre. - ~~ === -=-2-2-0+0-0-0eeec ec ec nsec eceeeeeeeereseee

1975 i 0.0000 240.9 15.8 45.9 6.0 0.0 0.0 0.0 6.0 0.0 00
1976 17 0.2129 102.5 16.8 56.0 45 89 23 17 13 21 17
1977 20 0.1889 119.0 93 55.4 4.0 15.4 22 45 1.0 33 3.5
1978 20 0.1849 101.9 12.5 42.0 6.0 98 54 2.0 23 1.6 44
1979 U 0.1829 89.6 10.7 20.4 6.4 63 3.6 2.6 16 1.6 14
1980 24 (0.1236 87.2 20 16.8 17 2.0 Ml 0.8 04 1.0 05
1981 21 0.2141 33.6 3.9 58 45 2.0 47 09 24 10 3.7
1982 2B 0.1559 30.1 8.7 6.7 47 0.9 40 0.5 23 22 16
1983 9 0.2901 23.0 70 0.0 26 09 1s 00 0.0 33 03
1984 7 0.3416 943.3 0.3380 309.1 736.2 309.1 198.4 0.0 73 0.0 14 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1985 8 0.2410 452.2 0.5200 90.1 354.4 83.3 98.2 0.0 0.0 13 16 17 0.0 13 0.0 08 Ml L7
1986 23 0.3154 233.1 0.4071 167.3 228.1 0 131.8 44 116 0.0 10.8 0.0 73 0.0 33 0.5 12 Ol 13
1987 29° 0.3160 189.6 0.2908 = 171.6 176.7 126.1 51 23.8 22 Md 1S 3.5 13 34 Lt 19 17 18
1988 36 0.4531 102.9 0.3357 174.7 82.2 143.8 97 15.2 53 88 32 48 04 08 OS 07 16 0.7
1989 377 0.3716 34.7 0.3500 124.8 24.7 87.2 0.0 19.2 5.2 8.6 19 5.4 12 1S 04 1 13 18
1990 42 0.3357 6.3 0.2739 145.7 00 113.4 0.0 13.8 2.0 98 13 37 1.3 20 08 10 08 20
1991 15 0.6519 13.8 0.3960 111.0 0.0 93.1 0.0 5.7 46 5.6 23 3.0 2.5 15 21 1.2 2.2 1.0

Allyears 353. 0.0737 339.3. 0.0734 336.5 195.9 292.4 89.6 25.5 35.7 8.7 124 43 31 25 12 13 AS 18

SE. 0.0737 0.0734 0.0979 0.0767 0.1063 0.1391 0.1017 0.1150 0.1205 0.1184 0.1496 0.1349 0.1578 0.1340 0.1686 0.1315

“Clearcut includes seed tree-shelterwood cuts, merchantable clearcuts, and all-tree clearcuts.

Pine types include longleaf-stash, loblolly-shortleaf, and oak-pine forest types.

Numbers in rows may not total due to rounding.

SMost recent harvest.

Number of sample plots in rows.

*"Sampling errors (one standard error) for column averages and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘Softwood species.

Hardwood species.


United States
Department of Agriculture

Forest Service

Southern Forest
Experiment Station

701 Loyola Ave., Am.T-10210
New Orleans, LA 70113-1931

OFFICIAL BUSINESS
Penalty for Private Use $300



Table 22.—Current density of softwood and hardwood for clearcut” oak-hickory type by year of harvest and diameter class, Louisiana, 1975-1991*

Diameter class
10-29 30-49 50-69 70-89 9.0-10.9 11.0-12.9 213.0
Year of, All as All = - - ~ - - -
harvest af SET soft” SE hard’ Soft” Hard't soft” Hard Soft” Hard’? Soft’ Hard't Soft” —Hard't Soft” Hard’? Soft" Hard‘?
a Number of trees per acre -

1975 2 0.1878 237.7 0.1286 16834 00 15128 00 1375 643 229 95.7
1976 1 0.0000 1L.1 0.0000 174.6 0.0 91.7 0.0 0.0 0.0 16.8 91
1977 2 05924 11322 02664 240.3 4286 2310 3774 «00-2026 «= 9396.0
1978 4 02003 6736 03585 349.0 2519 3218 2291 228 1272 00 S24
1979 3 0.6934 409.8 0.4586 8514 168.1 769.5 121 49 418 178 78.3
1980 4 03933 514.4 02625 710.3 1515 6816 184.2 212-1166 = 4.2504
1981 4 0.0720 363.5 0.4937 970.1 186.3 8899 1356 695 310 84 71
1982 8 0340 3143 0208 8739 1721 7575 549 769 809 195 50
1983 © 0.0000 00 0.0000 00 00 00 00 00 00 00 00
1984 4 0.9052 $26.9 0.6504 6856 3727 546.2 1416 155 54 24.9 29
1985 8 0.4992 804.3 0.3997 318.9 530.9 2950 2575 NS 4B 5H A'S
1986 3 05944 353.8 1.0000 282.7 351.1 2485 00 311 00 00 00
1987 9 0.4679 143.3 0.5738 95.1 109.3 76.2 20.1 10.1 59 19 39
1988 8 0.5347 5.4 0.3584 170.6 0.0 123.5 0.0 22 0.0 14 16
1989 5 08589 5.7 069%8 4719 00 4204 00 180 50 143 00 : ; x : . :
1990 9 09709 1354 03108 3005 1319 19%8 00 716 00 102 17 97 18 44 00 33 00 46
1991 508132, 3.705379 «164000 —s117.0- 00s 3-D_— 3.10.48 1106 OS
Allyears 790.1907 313.8 0.1388 469.3 «1775 4046 814384324 S SBR OSGHCOCSLC(“(tiCOTs—CBOS
se! 0.1907 0.1388 0.2303 0.1477 0.2552 0.1993 0.2168 0.2238 0.2974 0.1884 0.3425 0.2525 0.3773 0.2162 _ 0.2812 _ 0.2185

“Clearaut inctudes seed tree-shelterwood cuts, merchantable clearcuts, and all-tree clearcuts.

‘Numbers in rows may not total due to rounding.

‘Most recent harvest.

Number of sample plots in rows.

‘Sampling errors (one standard error) for column averages and row totals (on a telativized scale ranging from 0.0000 to 1.0000).
**Softwood species.

‘Hardwood species.


Table 17.—Current volume of softwood and hardwood for all forest types and all types of harvests by year of harvest and basal area class, Louisiana, 1975-1991

Basal area class (Square feet per acre)

<20 20-39 40-59 60-79 80-99 2100
Year of, All All -
harvest” at set soft SE? hard! Soft! Hard! Soft! Hard! Soft! Hard! Soft! Hard! Soft! Hard! Soft! Hard!
we etet ne eecee teense eeeece rene teceeeerecer sees Cubic feet per acre - -
1975 11 0.3204 687.6 0.1716 1.2084 00 00 00 00 929 9964 54.0 1715 186 1,705.2 1,169.7 1,105.5
1976 42 0.1409 889.6 0.1421 8195 0.00.0 296.2 253.8 «284.1 «404.3 765.8 «516.5 659.6 743.1 1341.2 1,162.8
1977 62 0.1062 9187 O.1I7L 8226 «= 0.0 00-272.2- 49.3. 297.2 457.2 863.1 652.7 687.9 1,064.2 1,274.1 792.5
1978 54 0.1370 759.0 0.1165 847.5 0.0 «209.6 «223.9 158.0 342.3. 447.0 396.9 605.8 492.9 1,059.5 1,272.3 1,046.4
1979 43 0.1569 754.7 0.1657 626.9 1909 0.0 216.6 = -GL.1_ S458 293.8 399.3 653.0 632.3 956.4 1,475.8 877.7
1980 11 0.0976 9114 0.1355 725.7 106.1 5.0 2409 © 69.3. 496.7 211.3 551.7 494.6 935.9 692.8 1,329.7 1,136.6
1981 56 0.1251 604.7 0.1200 5423 © 80.2. 84.7 268.7 149.0 319.2 469.2 $65.6 613.0 1,063.6 666.1 920.7 933.9
1982 64 0.1287 629.4 0.1338 «660.169.1580 245.4 «149.5 310.4 386.7 $90.5 455.2. 642.3 969.0 1,302.6 1,323.8
1983 QL 03621 379.6 0.2483 «780.0 «28.9 121.8 295.4 «31.8 178.0 702.8 «556.6 1,148.5 00 2,221.5 1,487.0 1,296.3
1984 25 0.2653 724.0 0.2085 084 705 323 292.2 136.2 5726 26.0 39.1 1,235.1 882.4 1,002.4 1,137.6 1,487.2
1985 25 0.2475 355.0 0.2380 3336 «© 54.7 53.9 246.3 198.2 3009 361.7 6338 617.6 514.2 913.3 1,901.3 220.1
1986 59 0.2366 456.6 0.1605 601.2 «59.2 16.5 72.3. 2127 «353.3 647.0 775.1 652.2 723.4 1,273.9 1,202.9 1,753.5
1987 135 0.1120 655.2 0.0957 509.1 281 = 56.4. 169.1 304.2 451.3 413.1 963.7 584.5 7304 1,100.7 1,584.7 1,302.5
1988 170 0.0910 7708 0.0781 601.0 568 53.5 1309 3387 381.2 523.1 576.0 837.2 1,268.8 739.8 1,946.5 959.7
1989 190 0.0809 784.7 0.0884 5022 13.2. 60.0 225.4 322.0 606.3. 411.3 1,010.9 573.2 1,278.2 796.1 1,791.9 990.9
1990 130 0.1162 619.4 0.1025 491.1 -25.9-«S7.3. 136.2 369.3. 376.6 620.0 943.3 649.6 1,259.9 844.0 1,838.9 993.4
1991 52 01661 672.1 0.1645 569.6 21133-23894 310.6 353.5 562.4 1.1803 466.6 890.3 8924 1,431.6 1,306.0
Allyears 1,216 0.0329 711.8 0.0316 6211 364 528 2160 2478 4252 461.8 7558 643.8 9083 9048 1,470.7 1,092.5
set 0.0329 0.0316 0.1455 0.1131 0.0849 0.0781 0.0763 0.0595 0.0558 0.0530 0.0588 0.0512 0.0412 0.0518
at 1,216 1,216 196 196 128 128 184 184 235, 235 217 217 256 256
“Most recent harvest.

Number of sample plots in columns and rows.

Sampling errors (one standard error) for column and row averages (on a relativized scale ranging from 0.0000 to 1.0000).

Softwood species.
Hardwood species.


Table 1.—A.rea of timberland harvested by year and type of harvest, Louisiana, 1975-1991"
Type of harvest

Clearcut
Year of All Seed tree or Merchantable All

harvest’ nt se! types Partial _ shelterwood trees trees Salvage

cette eee ee eee eee eee eee Thousand acres--- +++ +++ +200+200eeee eee ee
1975 rt 0.2886 68.2 41.0 0.0 15 19.8 0.0
1976 42 0.1552 233.1 108.3 55 523 67.0 0.0
1977 62 0.1257 352.5 210.1 28.7 288 79.3 55
1978 54 0.1360 302.1 150.3 0.0 48.8 919 11.0
1979 43 0.1513 245.1 96.3 30.6 28.6 84.0 5.7
1980 1 0.1110 448.9 269.7 27.4 322 120.0 0.0
1981 56 0.1332 315.0 130.5 18.2 85.4 69.9 11.0
1982 64 0.1209 380.3 158.9 16.6 344 1149 55
1983 21 0.2202 116.9 44.1 0.0 45.0 16.7 11.0
1984 25 0.2014 139.5 718 5.2 288 207 0.0
1985 25 0.1976 145.6 36.3 115 26.6 72 0.0
1986 59 0.1300 329.8 167.6 48 51.0 106.4 0.0
1987 135 0.0846 755.0 498.0 0.0 135.4 1116 10.1
1988 170 0.0749 950.3 652.8 215 150.6 102.5 228
1989 190 0.0703 1,068.8 715.6 218 140.0 119.6 11.8
1990 130 0.0857 T3718 414.4 119 205.0 106.6 0.0
1991 52 0.1367 299.1 180.0 16.6 74.5 28.0 0.0
All years 1,216 0.0206 6,888.0 4011.6 219.9 1,224.8 1,337.2 94.5
sé} 0.0206 0.0319 0.1599 0.0653 0.0622 0.2451
at 1,216 708 39 216 236 7

“Numbers in columns and rows may not total duc to rounding.

‘Most recent harvest.

Number of sample plots in columns and rows.

SSampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).

Table 2.—Area of forest industry timberland harvested by year and type of harvest, Louisiana, 1975-1991"

Type of harvest
Clearcut
Year of, All Seed tree or Merchantable All
harvest! at set __types Partial __ shelterwood trees trees Salvage
1975 3 0.5125 21.7 0.0 0.0 1S 14.2 0.0
1976 19 0.2280 109.0 17.0 55 39.6 47.0 0.0
1977 23 0.2071 132.0 43.2 16.2 6.1 61.0 5.5
1978 19 0.2322 105.1 34.1 0.0 10.3 55.2 55
1979 19 0.2243 112.6 18.5 30.6 6.2 573 0.0
1980 25 0.1963 146.7 60.7 5.5 21.0 59.5 0.0
1981 13 0.2805 72.2 16.2 0.0 23.0 33.0 0.0
1982 26 0.1884 159.2 43.0 12 25.0 80.1 0.0
1983 10 0.3106 58.9 12.9 0.0 29.3 112 5.5
1984 12 0.2963 64.8 314 5.2 11.0 171 0.0
1985 13 0.2721 76.7 0.0 0.0 11.0 65.7 0.0
1986 28 0.1883 159.3 79.8 0.0 28.7 50.8 0.0
1987 45 0.1486 253.9 143.9 0.0 53.0 57.0 0.0
1988 62 0.1261 350.0 245.4 5.4 45.6 48.0 57
1989 63 0.1259 351.4 246.9 54 16.9 82.1 0.0
1990 47 0.1438 2A 149.8 0.0 68.3 52.9 0.0
1991 24 0.2036 136.5 73.7 114 40.4 Ill 0.0
All years 451 0.0425 2,581.1 1,216.4 96.4 442.9 803.2 22.2
sEf 0.0425 0.0655 0.2426 0.1118 0.0819 0.5066
at 451, 214 17 71 139 4

“Numbers in columns and rows may not total due to rounding.
‘Most recent harvest.
+Number of sample plots in columns and rows.
‘Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).


1,500,

SS

wooo || | f
coe || Ue

SOFTWOOD VOLUME (CUBIC FEET/ACRE)

Y
rer eros
SFISRIAS

SAMPLE PLOT

WY

W

1982

SS

~ eR SHO x
2 & 2S S3H G
22 2.2222 a

YEAR OF MOST RECENT HARVEST

Figure 2.— Current softwood volume by year of harvest for stands that were
clearcut and were a pine type prior to harvest. Bars are one standard

error.

The number of hardwood trees drops off sharply, in
comparison to softwoods, beyond 3.0 inches in diameter.
By the time trees are moving into the 7.0- to 8.9-inch
diameter range, hardwoods have become a very minor
component. Table 20 can be used to illustrate the relative
time period for initial waves of the regenerating tree popu-
lation to reach specific size classes. In Louisiana, it is
taking approximately 6 to 7 years (after harvest) before an
appreciable number of softwood trees move into the 3.0- to
49-inch diameter range. It is taking 8 to 9 years for soft-
wood trees to reach the 5.0- to 6.9-inch range and 11 to 12
years to reach the 7.0- to 8.9-inch range. Additionally, these
stands are below the survey stocking standard for these
individual size classes. For example, there should be 340
t.p.a. of softwood trees in the 5.0- to 6.9-inch diameter
range for a stand to be 100 percent stocked, and 240 t.p.a.
in the 7.0- to 8.9-inch diameter range. No average ap-
proached either of these levels for stands harvested be-
tween 1975 and 1983. Instead, softwoods are spread out
over a wide range of diameter classes. For example, 72
percent of the total softwood density of stands harvested in
1982 was in the 1.0- to 2.9-inch diameter class. These are
stands harvested 9 years ago. This illustrates that late-es-
tablished softwood saplings made up the bulk of softwood
stocking. Overall, these clearcut stands appear adequately
stocked with softwoods when trees in all the 1.0- to 4.9-inch
diameter classes are included. However, time since harvest
should be considered when discussing adequacy of stocking
by size classes. Additionally, averages can be deceiving
because there will be values both below and above the
average that may affect the results of the analysis. For more

detailed information about the stocking condition of sap-
ling and seedling stands see Rosson, in press.

The yields in cubic-foot volume for clearcut pine types
show two different patterns (table 21). Softwood volume
increases as time since harvest increases (fig. 2). In con-
trast, hardwood volume increases very slightly and re-
mained, on an average, at less than 500 ft3/acre on all
clearcut pine type stands over the 17-year harvesting pe-
riod of this study (fig. 3). This indicates management op-
tions that favor softwoods.

The average performance of clearcut pine type timber-
land in the State is below that for normal stands on average
sites. Using loblolly pine as a comparison, 20-year-old
stands on normai sites (site index 90) average 1,900 to
2,200 fi3/acre for all trees greater than 3.6 inches in d.b.h.
(Burns and Honkala 1990). Although no stands in the
study were 20 years from harvest, none came close to the
1,900-ft3 standard, and no harvest-year average is expected
to reach that standard after 20 years from harvest. Addi-
tionally, this study included all softwoods greater than 1.0
inch in d.b.h., making the comparison even less favorable.
Stand age was not used in this study, only time since har-
vest. Therefore, true stand age may be anywhere from 2 to
7 years less than time since harvest.

Many of the oak-hickory stands that were clearcut sup-
port substantial amounts of softwoods. Softwood domi-
nance is especially evident in the 4.0-, 6.0-, and 8.0-inch
diameter classes (tables 22 and 23). The all-soft and all-
hard columns show that many clearcut oak-hickory stands
had enough density and volume in sofitwoods to be classi-
fied as a pine type at the time of the 1991 survey.


YZ WaRvESTED 1975 - 1986

HARVESTED 1987-1991

300

250

200

100

AREA OF OAK-HICKORY TYPE
(THOUSAND ACRES)
a
°
T

a
°
T

T
+
o Leen

ls

LONGLEAF-
SLASH

LOBLOLLY-
SHORTLEAF

OAK-PINE OAK-HICKORY

FOREST TYPE PRIOR TO HARVESTING

Figure 1.— Area of timberland currently in oak-hickory forest type by period of
harvest and forest type prior to harvesting. Bars are one standard

error.

converted to the loblolly-shortleaf pine type but lost sub-
stantially more acreage, 237,300 acres, into the oak—hick-
ory type. It appears that the selection of pine in partially
cut stands caused substantial shifts in forest type depend-
ing on the amount of pine volume removed. This, most
likely, resulted from leaving residual hardwoods as the
major component of these stands.

There are 1,881,900 acres of the harvested study popu-
lation currently in plantations, which is 27 percent of all
timberland harvested since 1975 (and in the study popula-
tion) (table 16). Of these plantations, the majority was
established on lands harvested between 1986 and 1990 and
between 1980 and 1982 (note, this is not the date of plan-
tation establishment). Most of the plantations were in the
loblolly-shortleaf pine forest type (59 percent).

Plantation acreage in the oak-pine and oak-hickory
forest types (389,700 acres) was most likely destined to be
in the loblolly-shortleaf pine or longleaf-slash pine forest
type. Explanations that may account for the 389,700 acres
not being in a pure pine type were stated earlier. Most of
this type of phenomenon are on recently harvested timber-
land. In addition, the plantations may have been hardwood
plantings. This is not likely, but the survey sample does not
distinguish between hardwood and softwood plantations.
These explanations are suggested because only a few thou-
sand acres in the oak—pine type remain in stands harvested
before 1982. It is plausible that these stands received less
intensive management and establishment practices, or that
it takes up to 10 years (in some stand situations) before
timberland targeted for plantations gains enough relative
pine stocking to be typed as loblolly-shortleaf or longleaf—
slash pine. It should be noted that even though pine stock-

ing is the plurality of the stand, the stand may still be
inadequately stocked relative to the survey stocking stand-
ard.

The current average volume for all timberland har-
vested since 1975 was 711.8 and 621.1 ft}/acre for soft-
woods and hardwoods, respectively (table 17). Average
volume for clearcut pine types was 384.9 ft3/acre for soft-
woods and 220.7 ft3/acre for hardwoods (table 18). Timber-
land harvested between 1975 and 1982 had the highest
volumes, as should be expected. This is because of the
length of time these stands have had to recover from cut-
ting.

Much of the clearcut oak-hickory type appeared to
have converted to a pine type (table 11). Many of these
stands harvested before 1986 had large proportions oftheir
volume in softwoods (table 19). There is ample evidence
suggesting this in the higher basal area classes. For exam-
ple, most oak-hickory stands with basal areas higher than
100 ft? and harvested before 1981 are now a pine type.
However, the small sample size for these years weakens the
inference that all clearcut oak-hickory stands are being
converted to pine types.

Current average densities for the clearcut pine types
reflect overall evenness between softwoods and hardwoods
at 339.3 and 336.5 t.p.a., respectively (table 20). This is
because high numbers of hardwoods are in the 1.0- to
2.9-inch diameter range, primarily due to their prolific
sprouting capability. However, from 3.0 inches in d.b.h.
and higher, the relative number of softwoods per acre is
much higher than hardwoods except for the first 6 years
after harvest.


Table 18.—Current volume of softwood and hardwood for clearcut’ pine types* by year of harvest and basal area class, Louisiana, 1975-1991

Basal area class (Square feet per acre)

Year of 1 4 <20 20-39 40-59 60-79 80-99 2100

ear Al Al ry - - - - o
harvest* at SE! soft” S.E% hard? Soft” Hard't_ Soft”” Hard" Soft’” Hard’? Soft”” Hard Soft”” Hard" Soft”” Hardt

: - Cubic feet per acre -

1975 1 0.0000 1126.4 0.000 1607 00 00 00 00 00 00 00 00 00 00 1,126.4 160.7
1976 17 0.1458 919.5 0.3282 280.4 0.0 0.0 385.7 54.1 427.1 123.5 607.9 374.2 968.4 165.2 1,429.2 493.4
1977 20 0.1236 1069.5 0.2407 3783 = 0.00.0 296.200 304.2 2985 = O21 ~—«IT1.2-««925.2 665.9 1,433.0 348.9
1978 20 0.1378 711.6 0.2129 4538 00 0.0 2822 546 4326 2355 523.1 391.7 512.0 711.9 1,189.6 605.9
1979 21 0.1716 611.3 0.2871 283.2 «1909 0.0 264.9 1.6 462.1 164.3 622.8 373.2 684.6 656.8 1,396.5 218.9
1980 24 0.1150 732.0 0.2384 134.6 106.1 5.0 316.6 0.0 428.6 207.0 687.4 «45.8 1,090.8 1888 13013 191.4
1981 21 0.1727 500.9 02184 317.5 80.2. 84.7 269.4 166.7 186.7 677.7 523.4 551.3 661.2 393.1. 1,279.4 209.3
1982 23 0.1784 455.8 0.2827 «263.6 «108.8 60.4 278.8 129.8 «419.1 «259.7 555.1 235.4 «542.8 834.0 2,003.2 134.6
1983 9 03399 4119 04792 904 196 00 2954 318 3505 1837 1,129.8 196.1 00 400 «00 8600
1984 7 02797 363.7 03802 435 1345 616 2519 463 5030 104 0.0 00 8708 487 00 00
1985 8 0.3096 2709 05318 878 866 361 39.5 1656 4789 132 00 00 00 00 00 00
1986 23 0.2447 © 46.6 0.4574 «207.0 56.7 18300000 945.00 909.3. 01,5400 0000
1987 29 0.4139 190.7 0.3284 245.1 «129 60.9 181.6 319.9 $37.0 69.6. = 0000—126.9 1,466.1 2,941.0 1,498.8
1988 36 0.3418 150.4 0.2524 119.4 33.3. 42001325 2228 «489.1 «371.3 1,009.8 3395 «00 sis
1989 37) 0.3654 = 131.0 0.4406 BBL. 15.1 38.0 357.6 173.0 458.9 453.7 0.0 0.0 0.0 0.0 0.0 2,886.5
1990 42 04718 83.0 0.2371 «185.327.0429 99.6 359.1 109.4 7359 «795.9 6909000 isiséiD
1991 15 0.5485 229.4 0.6105 133.5 44 29.1 13949 74 645.8 289.1 «6227 «6585S ii
All years 353 (0.0674 384.9 0.0858 220.7 «32.7 39.3. 277.7155. 403.4. 323.7 629.5 355.5 743.0 562.0 1,355.1 464.1
se! 0.0674 0.0858 0.1646 0.1430 0.1036 0.1506 0.1227 0.1520 0.0920 0.1678 0.0997 0.1644 0.0615 0.2066
af 353 353 4d 62 «62 42 42 39 39 33 33 36 36

“Clearcut includes seed tree-shelterwood cuts, merchantable clearcuts, and all-tree clearcuts.

*Pine types include longleaf-slash, loblolly-shortleaf, and oak-pine forest types.
‘Most recent harvest.

§Number of sample plots in columns and rows.

'Sampling errors (one standard error) for column and row averages (on a relativized scale ranging from 0.0000 to 1.0000).
‘Softwood species.

‘Hardwood species.


Appendix— Tables 1 through 23


Rosson, James F., Jr. 1994, Current stand characteristics of Louisiana
timberland harvested between 1975 and 1991, Res.Pap. SO-279. New
Orleans, LA: U.S. Department of Agriculture, Forest Service, South-
ern Forest Experiment Station. 22 p.

Commercially harvested timberland was analyzed by past and current
forest types, stocking, tree density, and volume. Monitoring sample
plots by year of harvest gives indications of rates and degree of recovery
from harvesting disturbance.

Keywords: Clearcut, cutting, disturbance, forest survey, regeneration,
stand establishment.



@

United States
Department of
Agriculture

Forest Service

Southern Forest
Experiment Station

New Orleans,
Louisiana

Research Paper
S0-279
January 1994

Current Stand Characteristics of
Louisiana Timberland Harvested
Between 1975 and 1991

James F. Rosson, Jr.


10

Table 5.—A rea of timberland harvested (all types of harvests) by year and current stocking class, Louisiana, 1975-1991"
Stocking class (range = 0 to 160 percent)

Year of, All
harvest" at SES classes <20 20-39 40-59 60-79 80-99 100-119 2120

1975 11 0.2886 68.2 0.0 0.0 0.0 18.1 18.1 26.4
1976 42 0.1552 233.1 0.0 0.0 0.0 46.9 122.4 47.0
1977 62 0.1257 352.5 0.0 5.5 0.0 98.7 114.2 120.4
1978 54 0.1360 302.1 0.0 0.0 54 679 134.4 944
1979 43 0.1513 245.1 0.0 0.0 ng 48.3 90.2 94.7
1980 77 0.1110 448.9 0.0 0.0 5.4 94.1 187.0 152.2
1981 56 0.1332 315.0 0.0 0.0 63 103.8 60.7 121.1
1982 64 0.1209 380.3 54 0.0 6.1 76.0 148.7 138.4
1983 2 0.2202 1169 0.0 55 0.0 117 38.4 45.2
1984 25 0.2014 139.5 0.0 0.0 5. 17.2 613 55.8
1985 25 0.1970 145.6 0.0 0.0 12.0 23.9 412 62.9
1986 59 0.1300 329.8 0.0 0.0 6.2 95.4 110.5 95.4
1987 135 0.0846 755.0 0.0 6.2 213 246.9 238.1 1613
1988 170 0.0749 950.3 5.2 5.2 16.9 303.2 309.9 191.7
1989 190 0.0703 1,068.8 10.9 6.0 55.8 333.7 336.3 190.7
1990 130 0.0857 7378 11.0 22.7 517 180.8 210.8 128.3
1991 52 0.1367 299.1 10.2 47 27.3 64.5 125.7 28.6

All years 1,216 0.0206 6,888.0 42.7 55.8 2314 1,831.1 2,347.8 1,754.5

set 0.0206 = 0.3651 (0.3193 0.1558 0.0521 0.0450 0.0534

at 1,216 8g 10 Al 325 410 310

“Numbers in columns and rows may not total due to rounding.

Most recent harvest.
Number of sample plots in columns and rows.

‘Sampling errors (one standard error) for column and row totais (on a relativized scale ranging from 0.0000 to 1.0000).

Table 6.—A rea of clearcut upland forest types that have regenerated naturally, by year and current softwood stocking class, Louisiana, 1975-1991"
Stocking class (range = 0 to 160 percent)

Year of, All
harvest’ at ses classes <20 20-39 40-59 60-79 80-99 100-119 2 120
cto e nena cee eceecee een eennnenl Thousand acres

1975 1 0.8721 15 0.0 0.0 0.0

1976 7 0.3915 372 56 16.0 39

1977 12 0.2870 69.0 52 123 5.8 12.5

1978 8 0.3591 442 6.1 16.7 5.2

1979 8 0.3526 45.8 10.7 56 15

1980 8 0.3724 41d 0.0 58 5A

1981 10 0.3113 58.7 17.7 23.6 57 .

1982 12 0.2820 m4 23.6 1S 0.0 16.3

1983 3 0.6014 15.8 0.0 0.0 tet

1984 4 0.4866 24.4 65 17 58

1985 2 0.7146 11.2 57 55 0.0

1986 7 0.3829 38.8 16.6 N12 0.0 r

1987 19 0.2318 105.5 36.8 22.8 276 18.3

1988 a 0.1931 151.6 84.7 22.1 5.5 23.2 .

1989 26 0.1967 146.0 83.8 35.0 15.9 0.0 114 0.0 0.0

1990 39 0.1585 223.6 168.1 214 23.8 10.4 0.0 0.0 0.0

1991 18 0.2375 100.5 83.1 116 0.0 59 0.0 0.0 0.0
Alll years 21 0.0662 1,192.1 554.2 228.7 122.9 120.1 19.6 nz 15.3
ses 0.0662 0.0995 0.1567 0.2147 O2171 0.2671 0.2825 0.6104
at 211 98 40 22 21 14 13 3

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest.

Number of sample plots in columns and rows.

Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).


Table 3.—Area of nonindustrial private timberland harvested by year and type of harvest, Louisiana, 1975-1991"

Type of harvest
Clearcut
Year of, All Seed tree or Merchantable All
harvest nt spt types Partial _ shelterwood trees trees Salvage
watt ee este ee rere eee ee Thousand acres----=+-- +++ -220++200--222eee
1975 8 0.3498 46.5 41.0 0.0 0.0 5.6 0.0
1976 18 0.2370 100.9 81.5 0.0 88 10.6 0.0
1977 32 0.1755 183.0 135.7 6.2 28 18.3 0.0
1978 3 0.1788 176.4 104.9 0.0 38.5 275 55
1979 22 0.2132 124.6 69.9 0.0 22.4 26.6 57
1980 45 0.1447 267.8 187.6 16.0 11.2 53.0 0.0
1981 38 0.1602 219.1 103.9 18.2 62.4 23.5 11.0
1982 38 0.1594 221.2 115.9 55 59.4 34.9 55
1983 9 0.3390 49.5 215 0.0 11.0 55 55
1984 MN 0.2954 65.2 41.6 0.0 13.1 10.5 0.0
1985 10 03111 58.8 29.8 5 ng 5.6 0.0
1986 a 0.1923 152.7 BS 48 2.3 51.8 0.0
1987 n 0.1153 417.0 286.0 0.0 48 49.9 62
1988 93 0.1013 535.5 351.1 16.1 100.5 50.6 71
1989 115 0.0903, 667.5 486.2 16.4 119.3 33.8 18
1990 2 0.1156 415.1 224.1 11.9 131.9 47.3 0.0
1991 26 0.1929 151.8 106.3 5.2 29.5 10.9 0.0
All years 667 0.0328 3,852.6 2,466.8 118 739.8 465.8 68.4
set 0.0269 0.0308 0.2090 0.0662 0.1430 0.1643
at 667 424 20 129 82 12
“Numbers in columns and rows may not total due to rounding.
‘Most recent harvest.
Number of sample plots in columns and rows.
‘Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
Table 4.—A rea of timberland harvested (all types of harvests) by year and current basal area class, Louisiana, 1975-1991"
Basal area class (Square feet per acre)
Year of, All
harvest’ a? se! classes <20 20-39 40-59 60-79 80-99 2100
Thousand acres- - - -
1975 rt 0.2886 68.2 0.0 0.0 63 1S 116 38.9
1976 42 0.1552 233.1 0.0 18.3 21.1 20.7 703 95.7
1977 62 0.1257 352.5 0.0 10.7 28.5 368 122.2 1543
1978 54 0.1360 302.1 54 19.9 271 513 Ba 125.0
1979 43 0.1513 245.1 5.7 30.1 51.9 28.9 618 66.7
1980 7 0.1110 448.9 5.7 17.8 57.2 94.6 102.5 1713
1981 56 0.1332 315.0 5.7 57.4 68.6 726 68.2 424
1982 64 0.1209 380.3 30.1 54.3 53.8 86.6 70.5 85.1
1983 2 0.2202 116.9 295 16.3 21.2 27 129 15.4
1984 25 0.2014 139.5 99 26.6 11.6 14 29 58.1
1985 25 0.1970 145.6 33.0 48.3 22.7 176 18.6 55
1986 59 0.1300 329.8 118.0 116 60.0 64.9 40.2 35.0
1987 135 0.0846 755.0 150.0 114.0 112.4 154.1 98.2 126.3
1988 170 0.0749 950.3 197.7 80.5 121.3 228.0 140.3, 182.5
1989 190 0.0703 1,068.8 210.1 1276 201.9 201.6 206.4 121.2
1990 130 0.0857 7378 231.1 63.1 122.8 168.7 BB 783
1991 52 0.1367 299.1 16.4 32.2 48.5 45.2 410 55.8
Allyears 1,216 0.0206 6,888.0 1,108.1 728.6 1,036.9 1,323.1 1,233.7 1,457.6
ses 0.0206 0.0689 0.0862 0.0714 0.0625 0.0650 0.0593
at 1,216 196 128 184 235 217 256

“Numbers in columns and rows may not total due to rounding.

Most recent harvest.

Number of sample plots in columns and rows.

‘Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).


1,500

1,000

500

HARDOOD VOLUME (CUBIC FEET/ACRE)

ONLY ONE SAMPLE PLOT

N 6 &©K ®HDO >
2 2 % G9 % DB
g seasass

YEAR OF MOST RECENT HARVEST

Figure 3— Current hardwood volume by year of harvest for stands that were
clearcut and were a pine type prior to harvest. Bars are one standard

error.

CONCLUSIONS

This study focused on 6,888,000 acres of timberland
that underwent some form of commercial harvesting be-
tween 1975 and 1991. The most common harvesting
method was partial harvesting (58 percent) followed by
clearcutting (37 percent). Most of the harvesting was done
on NIPF lands (56 percent).

Because the forest type classification reflects the domi-
nant species in a stand, it can be used to monitor broad
changes in stand composition. Specifically, in monitoring
the effects of harvesting disturbance, shifts in forest type
can be identified. In this study, interest was in how much
acreage shifted, after harvesting, from a pine type to the
oak-hickory type and, conversely, from the oak—hickory
type to a pine type.

Of the 1,996,400 clearcut acres of longleaf-slash pine,
loblolly-shortleaf pine, and oak-pine forest types,
1,483,100 acres are currently in a pine type, and 513,300
acres are in the oak-hickory type. Because of the time it
takes pines to surpass hardwoods in sample dominance,
much of this 513,300 acres in the oak—hickory type will
probably convert to a pine type. Currently, in Louisiana,
this is taking approximately 6 to 7 years.

On 3,315,200 acres of partial cut stands of longleaf—
slash pine, loblolly-shortleaf pine, oak-pine, and oak—
hickory forest types, 2,304,200 acres are in a pine type and
382,500 acres are in the oak-hickory type. If pine produc-
tion is the management goal, these 382,500 acres in the
oak-hickory type will need followup treatment for pine
establishment.

Louisiana has 905,800 and 383,200 acres of upland
clearcut timberland with < 60 percent softwood stocking in
naturally regenerated and plantation stands, respectively.
Approximately 22 to 30 percent of regenerating stands are
still < 60 percent stocked with softwoods 6 or more years
after harvesting.

It is taking approximately 6 to 7 years after harvest
before initial waves of regenerating softwoods are reaching
the 3.0- to 4.9-inch diameter range. Additionally, these
stands are below the survey stocking standard for this size
class. Although there is evidence in the data of manage-
ment favoring pine, average per-acre volumes for 15 years
after harvest are below the 1,900- to 2,200-ft3/acre standard
for normal sites (site index 90) at age 20. Accumulating 100
ft3/acre/year would still place these stands below 1,500 ft?
at 20 years from harvest. Low softwood stocking levels and
lengthy regeneration lag time after harvest are cited as two
reasons for this volume shortfall.

LITERATURE CITED

Burns, Russell M.; Honkala, Barbara H., tech coords.
1990. Silvics of North America: Conifers. Agric.
Handb.654. Washington, DC: U.S. Department of Ag-
riculture. 675 p. Vol. |.

Rosson, James F., Jr. [In press]. The status of precommer-
cial-sized softwoods in Louisiana, 1991. Res. Pap. SO-
278. New Orleans, LA: U.S. Department of
Agriculture, Forest Service, Southern Forest Experi-
ment Station.


Table 21.—Current volume of softwood and hardwood for clearcut” pine types' by year of harvest and diameter class, Louisiana, 1975-1991*

Diameter class
1.0-2.9 3.04.9 5.04.9 70-89 9.0-10.9 11.0-12.9 213.0
Year of, All ~All
harvest? nt SE” soft i hard’ Soft Hard'* Soft’ Hard'? Soft!" Hard*? Soft! Hard**soft't Hardt Soft't Hard Soft" Hara**
: Cubic feet per acre
1975 1 0.0000 1126.4 0.0000 1607 140 110.7 4615 0.0 489.5 500 1614 0000s isis
1976 17 0.1458 919.5 0.3282 2804 © 64.7 95.0 205.4 543-2294 29.1 242.4206 «= 726-164 29.5 16.6 5S AB A
197 20 0.1236 1069.5 0.2407 3783 429 «1381 «171.5 74.E 261.0 13.9 2589 1821294206 67.1124 1386 101.
1978 20 0.1378 711.6 0.2129 453.8 27.0 114.1 142.5 81.9 205.3 29.4 1758247 72D ALS 320-322 56.8 129.9
1979 21 0.1716 611.3 0.2871 283.261.0787 = «126.6. $4.2 1440 23,3 89.5 28S $73 387 46.7 21.8 865.2379
1980 24 0.1150 732.0 0.2384 134.6 69.5, 118 379.6 28.3 153.4 42 67.1 4.1 19.8 9.7 13.6 6.4 29.1 10.4
1981 210.1727 5009 0.2184 317.5 548 95.3 265.5 40S S24 7427.7 19-2 20.4 33.0 15.9 ROLL (94.2
1982 23 (0.1784 455.8 0.2827 2636 126.2 57.6 164.2 306 = 47.4 1722S 36.0 24.0 89 418 6.6 «326 6S 59.7
1983 9 03399 4119 0.4792 904 680 314 1725 110 20 255 00 55 102 136 00 00 1322 34
1984 7 0.2797 = 363.7 0.3802 43.5 154.9 43.5 193.7 0.0 6.3 0.0 89 0.0 0.0 0.0 0.0 0.0 0.0 00
1985 8 0.3096 270.9 0.5318 878 «112 «847.5 000383 5B 99 730TH
1986 23 0.2447 46.6 0.4574 «207.0296 21.6 26 105 00 «26.7 = 0036.6 00 39.99.3227 SB
1987 29 0.4139 190.7 0.3284 245.1 23.9 19.2 34° S15 6.3 24.8 13.6 22.2 16.1 36.2 24.8 27.1 100.6 64.1
1988 36 03418 150.4 0.2524 1194 122 187 110 183° 181 87-22-7238 40 61 129-63 69.4274
1989 370.3654 131.0 0.4406 181 4119.4 00 221 160 155 112 240 135 108 119 148 744 746
1990 42 04718 83.0 0.2371 «1853 0.0 30200205 51 198 = 87 17.2 19.4 20.1 200134 29.764
1991 15 05485 229.4 06105 1335 0.0207 00 44 86 139 10184 25.3 17.3364 23.6 4B 35.2
All years 353 0.0674 384.9 0.0858 220.7 40.1514 100.4 329 69.8) 18.2 S71 20582 23.0L2ST.T—s—=ié«ANSC*«*STON
SE” 0.0674 0.0858 0.0985 0.0812 0.1089 0.1519 0.1047 0.1232 0.1209 0.1236 0.1445 0.1491 0.1588 0.1441 0.1738 0.1542

“Clearcut includes seed tree-shelterwood cuts, merchantable clearcuts, and all-tree clearcuts.
‘Pine types include longleaf-siash, loblolly-shortleaf, and oak-pine forest types.
Numbers in rows may not total due to rounding.
SMost recent harvest.
Number of sample plots in rows.
“Sampling errors (one standard error) for column averages and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘Softwood species.
Hardwood species.


normal yield tables of average stocking levels found in
natural uncut stands. The survey standard was derived by
reducing these normal stocking averages to averages found
on recently cut areas judged to be well managed. Thus, the
stocking standard used by the forest survey represents
about 50 to 70 percent of normal stocking for pole- and
sawtimber-sized stands. The sapling and seedling tree
standard was reduced even further to less than 50 percent
below normal stocking. Originally set at 1,000 trees per
acre (t.p.a.), it was revised to 600 t.p.a. in the 1960's to
reflect standards based on new studies of southern forests.
Reasons for adopting standards so much lower than nor-
mal for small trees were based on the well-recognized
tendency for young forest stands of varying stocking levels
to reach or approach normal stocking as they grow older.

The arbitrary levels of stocking used in this paper were
based on this stocking standard. Stands < 60 percent
stocked with softwoods were considered understocked,
stands stocked with > 60 but < 120 percent softwoods were
considered fully stocked, and stands > 120 percent stocked
with softwoods were considered overstocked. References
to Louisiana’s timberland being understocked or over-
stocked imply comparison to this stocking standard of tim-
ber production, in this case, softwood timber production.
It is recognized that many owners will have different objec-
tives, both economically and aesthetically. Portions of this
paper serve only as a vehicle to demonstrate realized (or
unrealized) softwood production based on the stocking
standard described.

The year of harvesting for the plot was derived by sub-
tracting the elapsed time (since sample trees had been cut)
from the date of sample plot measurement. In some cir-
cumstances, trees on the same plot had different removal
times, These plots were given an average removal year that
was derived by weighting the elapsed time with the tree’s

Table I.—Current stocking standard for the South, by tree size

Diameter class” Stocking standard
Inches Trees per acre

<l 600

2 560

4 460

6 340

8 240
10 155

12 us
4 90
16 72
18 60
20 51
22 42
a 36
26 31
28 27
30+ 24

“In increments of 2 inches; i.e., the 6-inch diameter class
includes stems 5.0-6.9 inches in diameter.

importance (size and number of trees per acre that the tree
represented). Another special circumstance involved plots
that had harvesting activity within the plot boundaries but
where no sample trees were affected. The harvest date for
these plots was given as the median year between survey
periods. One final adjustment was made to these data. A
total of 1,216 plots was designated as harvested in either
the 1984 or 1991 survey period. A portion of these (223
plots) was recorded as harvested in both survey periods.
For purposes of analysis, these plots were given their re-
spective harvest date only in the 1991 survey period (1985
to 1991) because this represents the most recent distur-
bance to the plot that affected the major points of analysis
in this study.

The year of harvesting for each plot was based on the
removal time of individual sample trees. The removal time
that field personnel assigned to cut trees was a subjective
assessment. Certain guidelines were used in the assign-
ment of removal time: (1) age and condition of sprouts, (2)
status of annual rings on trees still standing (sign of re-
lease), (3) condition of cut face of stump, (4) bark condi-
tion on stump, (5) condition of logging slash, and (6)
occurrence of fungi and subsequent extent of development.
Obviously, the estimates of removal times for recent cut-
tings are very good, but the inference becomes weaker as
the time period lengthens.

Forest types were assigned quantitatively according to
the relative stocking of the most dominant trees. Owner-
ships were designated by the use of courthouse records.
Type of harvesting was assigned to each plot by field per-
sonnel. Some judgment was needed to separate commer-
cial harvesting from forest management practices (such as
thinning). Harvesting categories assigned in the field were:
(1) partial harvest, (2) seed tree/shelterwood cuts, (3)
clearcuts of merchantable trees, (4) complete clearcuts,
and (5) salvage cuts. To simplify some tables and discus-
sion, salvage cuts and partial harvests were combined into
one category (partial harvesting) and seed tree/shelter-
wood cuts, merchantable clearcuts, and all-tree clearcuts
were combined into a second category (clearcutting).

Additional restraints on the data set were that a plot
had to be forested in both the 1984 and 1991 surveys.
Reversions and diversions in the 1991 data set were not
included in the study.

RESULTS AND DISCUSSION

A total of 8,159,900 acres of timberland underwent
some form of commercial harvest between 1975 and 1991.
Some of this acreage, 1,271,900 acres, was harvested to
some degree in both the 1975 to 1984 and 1985 to 1991
survey periods. In order to capture the most recent harvest-
ing disturbance episode for this study, these particular
stands were assigned their respective harvesting year only
in the 1985 to 1991 survey period. This resulted in a total


Table 11.—Area of clearcut oak-hickory forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type
Year of All Longleaf-slash Loblolly-shortleaf Bottomland
harvest’ at set types pine pine Oak-pine Oak-hickory hardwoods + Nontyped®
wes ee eee cee eee eee eet eeee Thousand acres ~~~ -- === 2-- 2-2 eee ee ee erences

1975 2 06165 15.0 0.0 15.0 0.0 0.0 0.0 0.0
1976 10,0000 5.6 0.0 0.0 0.0 0.0 56 0.0
1977 2 0.7330 106 0.0 10.6 0.0 0.0 0.0 0.0
1978 4 0.5070 22.2 0.0 16.7 5.5 0.0 0.0 0.0
1979 3 0.5671 177 0.0 122 0.0 56 0.0 0.0
1980 4 04890 23.8 0.0 18.1 58 0.0 0.0 0.0
1981 4 04947 23.3 0.0 5A 119 63 0.0 0.0
1982 8 0.3446 41.9 0.0 19.0 17.2 5.5 63 0.0
1983 0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1984 4 0.4891 23.8 0.0 61 0.0 11.2 65 0.0
1985 8 0.3546 45.3 0.0 39.6 0.0 5.7 0.0 0.0
1986 3 0.5649 17.9 0.0 5.6 12.3 0.0 0.0 0.0
1987 9 03349 50.7 6.2 22.8 6.1 103 54 0.0
1988 8 03582 44.4 5.2 5.5 5.5 16.7 14 0.0
1989 5 04508 28.0 0.0 5.1 0.0 17.4 5.5 0.0
1990 9 0.3302 $2.2 0.0 55 16.3 24.9 5.5 0.0
1991 504381 29.7 0.0 0.0 0.0 23.6 6.1 0.0

Alll years 79° 0.1098 458.3 114 186.7 80.6 127.2 52.3 0.0

sEf 0.1098 0.7065 0.1737 0.2655 0.2109 0.3297 0.0000

at 79 2 32 14 2 9 0)

“Numbers in columns and rows may not total due to rounding.

Most recent harvest.

+Number of sample plots in columns and rows.

‘Sampling errors (one standard error) for column and row totals (on a telativized scale ranging from 0.0000 to 1.0000).
‘Stands with 0.0 percent stocking; ie., no live trees in sample.

Table 12.—Area of partial cut longleaf-slash pine forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type

Year of, All Longleaf-slash Loblolly-shortleaf Bottomland
harvest* at SES types pine pine Oak-pine Oak-hickory hardwoods + Nontyped?
1975 00,0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1976 10,0000 5.4 0.0 5.4 0.0 0.0 0.0 0.0
1977 4 05298 = 20.3 20,3 0.0 0.0 0.0 0.0 0.0
1978 0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1979 Oo 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1980 5 0.4501 28.1 28.1 0.0 0.0 0.0 0.0 0.0
1981 1 0.0000 6.1 6.1 0.0 0.0 0.0 0.0 0.0
1982 3 0.5923 16.3 16.3 0.0 0.0 0.0 0.0 0.0
1983 0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1984 0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1985 0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0 0.0
1986 2 06822123 6.2 0.0 0.0 6.1 0.0 0.0
1987 5 0.4786 24.9 24.9 0.0 0.0 0.0 0.0 0.0
1988 8 0.3703 41.5 32.3 55 37 0.0 0.0 0.0
1989 18 0.2385 99.7 70.0 12.7 17.0 0.0 0.0 0.0
1990 12 02911 67.1 67.1 0.0 0.0 0.0 0.0 0.0
1991 1 0.0000 15 75 0.0 0.0 0.0 0.0 0.0

All years 60 0.1302, 329.2 278.8 23.6 20.8 61 0.0 0.0

se! 0.1302 0.1417 0.4911 0.5243 0.0000 0.0000 0.0000

at 60 51 4 4 1 0) 0)

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest,

Number of sample plots in columns and rows.

‘Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘Stands with 0.0 percent stocking; i., no live trees in sample.

13


Table 15.—Area of partial cut oak-hickory forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type
Year of, ‘All Longleaf-slash  Loblolly-shortleaf Bottomland
harvest" a? sES types pine pine Oak-pine_Oak-hickory _ hardwoods __Nontyped!
- Thousand acres - -
1975 4 0.4907 23.7 0.0 0.0 0.0
1976 00,0000 0.0 0.0 0.0 0.0
1977 7 0.3671 42.3 0.0 110 13.8
1978 5 04349 30.1 0.0 0.0 179
1979 2 Om 112 0.0 0.0 00
1980 4 0.4831 24.4 0.0 00 5.2
1981 3 0.5959 16.1 0.0 5.1 Sa
1982 3 0.5945 16.1 0.0 0.0 5.5
1983 oO 0.0000 0.0 0.0 0.0 0.0
1984 4 05007 22.7 0.0 0.0 6.1
1985 © 0.0000 0.0 0.0 0.0 0.0
1986 3 05942 16.2 0.0 0.0 0.0
1987 15 02620827 0.0 55 33.7 33.3
1988 2002255 LS 0.0 94 124 68.1
16 0.2469 93.1 0.0 0.0 22.4 46.1
6 04000 35.6 0.0 0.0 56 30.0
S| 04447 288 0.0 oo 63 17.0
97 0.0995 554.6 0.0 31.0 133.9 283.0
0.0995 0.0000 0.4289 0.2056 0.1406
97 ° 6 23

{Numbers in columns and rows may not total due to rounding.
[Most recent harvest.

+Number of sample plots in columns and rows.

{sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘Stands with 0.0 percent stocking; ie, no live trees in sample.

Table 16.—Area of harvested (all types of harvests) timberland presently in plantations by year of harvest and current forest type,
Louisiana, 1975-1991"

Forest type

Year of, All Longleaf-siash — Lobloll Bottomland
harvest" at spf types _pine Oak-pine _Oak-hickory hardwoods __Nontyped?
1975 2 0.6337 14.2 0.0 14.2 0.0 0.0 0.0 0.0
1976 12 0.2871 69.0 11.2 57.8 0.0 0.0 0.0 0.0
1977 13 02781 = 73.5 10.4 63.1 0.0 0.0 0.0 0.0
1978 18 02412975 10.8 57.9 23.0 58 0.0 0.0
1979 16 0.2487 91.7 34.8 46.0 58 5.1 0.0 0.0
1980 26 0.1932 «151.5 28.5 110.9 12.1 0.0 0.0 0.0
1981 19 0.2351 102.6 16.0 68.7 178 0.0 0.0 0.0
1982 26 0.1909 155.0 16.3 110.5 22.7 0.0 54 0.0
1983 6 0.4037 35.0 Md 16.4 0.0 1S 0.0 0.0
1984 8 0.3631 43.2 0.0 38.5 0.0 4.7 0.0 0.0
1985 14 0.2657 80.5 0.0 80.5 0.0 0.0 0.0 0.0
1986 26 0.1964 146.6 124 719.9 325 21.8 0.0 0.0
1987 350.1692 196.8 33.2 103.2 30.9 24.0 55 0.0
1988 36 0.1679 199.7 50.9 92.7 44.3 11.8 0.0 0.0
1989 45 0.1495 250.9 66.7 118.2 49.4 10.7 6.0 0.0
1990 270.1899 156.6 56.2 52.7 29.2 18.6 0.0 0.0
1991 305658 178 0.0 59 54 65 0.0 0.0

All years 332 (0.0513 1,881.9 358.4 1,116.8 IBA 116.6 17.0 0.0

set 0.0513 0.1246 0.0686 0.1432 0.2204 0.5795 0.0000

at 332 64 197 48 20 3 0

“Numbers in columns and rows may not total due to rounding.
‘Most recent harvest.
Number of sample plots in columns and rows.
qSampiing errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
‘Stands with 0.0 percent stocking: i, no live trees in sample.



Current Stand Characteristics of Louisiana Timberland
Harvested Bet ween 1975 and 1991

James F. Rosson, Jr.

INTRODUCTION

As the difference between tree growth and removals in
Louisiana narrows, future inventory levels of available for-
est resources will be dependent on the disposition of tim-
berland after harvesting operations. The timeliness and
adequacy of regeneration on harvested lands will become
increasingly important as the demand on timber resources
shortens harvesting cycles and includes more and more of
the resource base in harvesting activity. It therefore be-
comes critical that regeneration trends are monitored on
harvested timberland so that steps may be taken to ensure
adequate regeneration in both quantity and timeliness.

This study was conducted to serve as a pilot in assessing
the status and characteristics of Louisiana timberland har-
vested between 1975 and 1991 and for other Midsouth
States as surveys are completed. First, the area of timber-
land harvested was assessed by the type of harvest method
and year of most recent harvest. Next, softwood regenera-
tion on harvested timberland was determined by analyzing
the occurrence of change in current forest types from forest
types prior to harvesting. Most of the analysis centers on
clearcut forest types that had more than 25 percent stock-
ing in pine (longleaf-slash, loblolly-shortleaf, and oak-
pine). Last, a portion of this study was in the analysis of
stand performance (tree density and accumulation of soft-
wood volume by diameter class as of the 1991 survey date)
on clearcut timberland since the year of most recent har-
vest. Analyzing tree densities and volume accumulation
since the year of harvest gives an indication of the rate and
degree of recovery from harvesting disturbance.

Tables 1 through 21 are provided in the appendix to
supplement the analysis and provide resource information.
All tabular data are presented by the year of most recent
harvest. The tables provide information on timberland
area by type of harvest (tables 1-3), stocking (tabies 4-7),
clearcut timberland by forest types (tables 8-11), partial
cut timberland by forest types (tables 12-15), harvested
timberland currently in plantations (table 16), current vol-
ume and tree density of harvested timberland by basal area
classes (tables 17-19), and current volume and tree density
of harvested timberland by diameter classes (tables 20-23).

METHODS

Data from the 1984 and 1991 Louisiana forest surveys
were used in this study. The USDA Forest Service, South-
ern Forest Experiment Station, headquartered in New Or-
leans, Louisiana, administers the survey; the work unit
responsible for conducting the survey is the Forest Inven-
tory and Analysis (FIA) unit, located in Starkville, Missis-
sippi.

The sample design consisted of a two-phase method
involving dot counts for timberland area estimation and
tree measurements on sample plots for stand estimates and
tree attributes. Sample plots were located on a 3-mile
square grid and were revisited during successive invento-
ries. At each plot location, a 5-point satellite plot and a
10-point satellite plot were sampled for the 1984 and 1991
surveys, respectively. Trees 25.0 inches in diameter at
breast height (d.b.h.) were selected with a 37,5-basal area
factor prism. Saplings (trees > 1.0 inch and < 5.0 inches in
d.b.h.) were measured on 7.1-foot radius plots at satellite
points 1,2, and 3. Saplings were also tallied (to supplement
stocking assessment only) on points 4 through 10 if less
than two live trees 2 5.0 inches in d.b.h. were sampled at a
specific point. Stocking is expressed as the relative meas-
urement (in percent) of sampled stand density (based upon
the aggregation of individual tree density) to the specified
density given in table I. Seedlings (trees < 1.0 inch in d.b.h.)
were tallied on points 1 through 10 where no live trees
2 1.0 inch in d.b.h. occurred in the respective point sam-
ple.The sampling procedure was based on the premise of a
theoretical maximum plot stocking of 160 percent. There-
fore, each satellite point in the sample could not have over
16 percent stocking. This carries implications to the seed-
ling and sapling sample. Only the four most dominant
seedlings or saplings were tallied per point because of the
i6-percent stocking assignment limitation. Therefore,
complete enumerations of seedlings were not done in the
sample. Complete sapling enumerations were done on sat-
ellite points 1, 2, and 3 but not on points 4 through 10.

The stocking standard in table I (developed in the
1950’s by a consortium of forestry professionals from in-
dustry and government) was based on basic references for

James F. Rosson, Jr., is a research forester at the Forest Inventory and Analysis unit, U.S. Department of Agriculture, Forest Service, Southern Forest

Experiment Station, Starkville, MS 39759.


The United States Department of Agriculture (USDA) prohibits discrimination
in its programs on the basis of race, color, national origin, sex, religion, age,
disability, political beliefs,and marital or familial status. (Not all prohibited bases
apply to all programs.) Persons with disabilities who require alternative means for
communication of program information (braille, large print, audiotape, etc.)
should contact the USDA Office of Communications at (202) 720-5881 (voice) or
(202) 720-7808 (TDD).

To file a complaint, write the Secretary of Agriculture, U.S. Department of
Agriculture, Washington, D.C. 20250, or call (202) 720-7327 (voice) or (202)
720-1127 (TDD). USDA is an equal employment opportunity employer.

*U.S. GOVERNMENT PRINTING OFFICE: 1994-565-016/80043


SUMMARY

A study population, using 1,216 forest survey continuous forest inventory
(C.F.L) plots, was constructed to analyze the current stocking trends and perform-
ance of timberland harvested in Louisiana between 1975 and 1991. A total of
6,888,000 acres was harvested; 4,011,600 acres by partial harvest, 219,900 acres by
seed tree and shelterwood methods, 2,562,000 acres by clearcut, and 94,500 acres by
salvage cut.

Of the 2,454,700 acres of clearcut upland forest types, 640,500 acres converted
to the oak-hickory type. It is taking 6 to 7 years, after harvesting, for softwoods to
reach the 3.0-inch diameter threshold. Additionally, softwood stand volume 13 to 17
years after clearcut harvest is below that expected for normal sites. Low softwood
stocking levels and lengthy regeneration Jag time are cited as two possible reasons
for low yields at this stage of stand development.


Table 7.—A rea of clearcut upland forest types that are currently in plantations, by year and current softwood stocking class, Louisiana, 1975-1991"

Stocking class (range = 0 to 160 percent)

Year of, Al

harvest’ nt spf classes <20 20-39 40-59 60-79 80-99 100-1192 120
- Thousand acres -

1975 2 0.6337 14.2 0.0 0.0 0.0 0.0 67 0.0 15
1976 ul 0.2991 63.6 0.0 0.0 0.0 16.0 18.6 71 118
1977 10 0.3164 56.8 0.0 0.0 0.0 22.4 10.7 10.7 13.0
1978 16 0.2575 85.6 0.0 16.8 106 Sa 37.1 10.7 3.2
1979 16 0.2487 91.7 5.1 5.7 12.0 16.6 22.4 23.6 63
1980 20 0.2211 115.9 0.0 0.0 5.6 29.4 36.0 217 23.2
1981 15 0.2630 82.1 0.0 0.0 0.0 23.2 316 5.7 216
1982 19 0.2219 115.0 0.0 114 114 18.3 6.1 43.7 243
1983 6 0.4037 35.0 15 0.0 0.0 0.0 5.5 10.7 112
1984 7 0.3896 37.5 0.0 47 0.0 5.2 0.0 10.6 17.0
1985 14 0.2657 80.5 0.0 0.0 0.0 26.7 25.0 225 63
1986 19 0.2289 108.2 11.9 22.8 214 18.1 22.8 5.7 5.5
1987 19 0.2290 108.1 6.1 125 233 30.5 25.0 5.2 $5
1988 17 0.2430 96.0 6.2 16.4 45.3 16.3 11.8 0.0 0.0
1989 16 0.2533 88.4 10.7 213 23.2 15.7 175 0.0 0.0
1990 12 0.2808 721 58 253 28.2 63 6.5 0.0 0.0
1991 2 0.6907 12.0 6.5 0.0 5.4 0.0 0.0 0.0 0.0
All years 221 0.0642 1,262.7 59.9 137.0 186.3 249.7 283.5 187.8 158.5
ses 0.0642 0.3083 0.2032, 0.1739 0.1499 0.1405 0.1732 (0.1888
_ 221 10 24 33 44 50 33 27

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest.

Number of sample plots in columns and rows.

‘Sampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).

Table 8.— Area of clearcut longleaf-slash pine forest type by year of harvest and current forest type, Louisiana, 1975-1991"
Forest type

Year of, All Longleaf-slash — Lobloll Bottomland
harvest’ at sei types pine pine Oak-pine Oak-hickory hardwoods —_Nontyped!

1975 © 0.0000 0.0 0.0 0.0 0.0 0.0 0.0
1976 5 0.4650 (26.4 1.2 113 39 0.0 0.0
1977 2 0.7249 10.9 0.0 10.9 0.0 0.0 0.0
1978 2 0.7256 10.8 108 0.0 0.0 0.0 0.0
1979 7 0.3803 39.4 28.6 5.7 0.0 5.1 0.0
1980 6 03996 35.7 175 18.2 0.0 0.0 0.0
1981 3 06165 ~=—-15.0 9.8 0.0 5.2 0.0 0.0
1982 1 0.0000 6.1 0.0 61 0.0 0.0 0.0
1983 10,0000 55 55 0.0 0.0 0.0 0.0
1984 10,0000 5.2 0.0 5.2 0.0 0.0 0.0
1985 10,0000 55 0.0 5.5 0.0 0.0 0.0
1986 10,0000 6.2 6.2 0.0 0.0 0.0 0.0
1987 3 0.5722 17.4 118 5.7 0.0 0.0 0.0
1988 6 0.4181 32.6 17.2 0.0 10.2 5.2 0.0
1989 8 0.3556 45.0 0.0 16.8 WS 5.5 5.2
1990 4 0.5022 22.6 0.0 5.2 0.0 17.4 0.0
1991 0 0.0000 0.0 0.0 0.0 0.0 0.0 0.0

All years 510.1403 284.3 118.7 90.3 36.8 33.2 5.2

set 0.1403 0.2185 0.2507 0.3932 0.4140 0.0000 0.0000

at 51 21 16 7 6 0) 1

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest.

Number of sample plots in columns and rows.

SSampling errors (one standard errot) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
TStands with 0.0 percent stocking; i.e., no live trees in sample.



Table 13.—Area of partial cut loblolly-shortleaf pine forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type
Year of, : ' ‘All Longleaf-slash  Loblolly-shortleaf Bottomland
harvest SE, types pine pine Oak-pine _Oak-hickory hardwoods _Nontyped'
ween eee ce eee cee n ene eree neon Thousand acres :
1975 1 0.0000 5.8 0.0 0.0 0.0
1976 6 04185 32.5 0.0 18.1 89
1977 9 03335 51.2 0.0 327 18.5
1978 1003141 57.7 0.0 40.8 Ml
1979 8 0.3548 45.2 0.0 29.4 10.2
1980 13 0.2685 78.8 0.0 56.2 119
1981 13. 02782 73.4 0.0 51.3 16.6
1982 10 0.3111 58.8 0.0 40.9 7.9
1983 2 0.6992 7 0.0 0.0 11.7
1984 4 0.5094 22.0 0.0 22.0 0.0
1985 10.0000 6.2 0.0 0.0 6.2
1986 10 0.3202 55.5 0.0 40.5, 11.2
1987 420.1541 236.4 124 126.0 747
1988 54 0.1373 296.6 6.7 242.2 25.4
1989 61 O.27t (344.9 0.0 227.3 722
1990 32 O.1761—«181.8 55 101.7 52.6
1991 14 0.2736 75.9 0.0 64.9 11.0
All years 290 0.0556 1,634.3 24.4 1,094.0 359.9 139.1 17.0 0.0
SES 0.0556 0.4839 0.0694 0.1244 0.2017 0.5794 0.0000
at 290 4 194 64 25 3 0

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest.

Number of sample plots in columns and rows.

SSampling errors (one standard error) for column and row totals (on a rel:
Istands with 0.0 percent stocking; i.e., no live trees in sample.

vized scale ranging from 0,0000 to 1.0000).

Table 14.—Area of partial cut oak-pine forest type by year of harvest and current forest type, Louisiana, 1975-1991"

Forest type
Year of, All Longleaf-slash — Loblolly-shortleaf Bottomland 4
harvest! a? set types pine pine Oak-pine Oak-hickory hardwoods —_Nontyped’
- -Thousand acres -

1975 0 0.0000 0.0 0.0 0.0 0.0
1976 5 0.4330 30.4 0.0 0.0 24.8
1977 6 0.4133 33.4 0.0 16.9 5.1
1978 7 03814 39.2 0.0 10.5 5.6
1979 4 0.4833 244 0.0 0.0 12.6
1980 12 0.2849 70.0 0.0 23.2 30.2
1981 4 0.5040 22.4 0.0 0.0 5.6
1982 7 03599 44.0 0.0 0.0 23.8
1983 2 0.7868 9.2 0.0 5.5 0.0
1984 2 06683 «12.8 0.0 0.0 12.8
1985 2 0.7296 = 10.7 0.0 0.0 10.7
1986 10 0.3242 54.1 0.0 113 16.9
1987 16 0.2488 917 0.0 23.7 33.0
1988 16 0.2451 94.5 0.0 34.2 314
1989 27° (0.1952 148.3 58 49.5 518
1990 13° 0.2914 «67.0 0.0 0.0 34.0
1991 703555 45.0 0.0 5.9 18.0 21.2

All years 140 (0.0822, 797.1 58 180.6 316.3 237.3

set 0.0822 0.0000 0.1767 0.1329 0.1538

at 140 1 32 55 42

“Numbers in columns and rows may not total due to rounding.

‘Most recent harvest.

Number of sample plots in columns and rows.

SSampling errors (one standard error) for column and row totals (on a relativized scale ranging from 0.0000 to 1.0000).
Stands with 0.0 percent stocking; i.e., no live trees in sample.