United States

Department of

Agriculture

Forest Service

Pacific Northwest

Research Station

Research Paper

PNW-RP-563

March 2005

Spruce Reproduction

Dynamics on Alaska’s

Kenai Peninsula,

1987-2000

Willem W.S. van Hees
The Forest Service of the U.S. Department of Agriculture is dedicated to the

principle of multiple use management of the Nation’s forest resources for sustained

yields of wood, water, forage, wildlife, and recreation. Through forestry research,

cooperation with the States and private forest owners, and management of the

National Forests and National Grasslands, it strives—as directed by Congress—to

provide increasingly greater service to a growing Nation.

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USDA is committed to making the information materials accessible to all USDA

customers and employees

Author

Willem W.S. van Hees is a research forester, Forestry Sciences Laboratory, 3301

C St., Suite 200, Anchorage, AK 99503. bvanhees@fs.fed.us
Abstract

van Hees, Willem W.S. 2005. Spruce reproduction dynamics on Alaska’s Kenai

Peninsula, 1987-2000. Res. Pap. PNW-RP-563. Portland, OR: U.S. Department

of Agriculture, Forest Service, Pacific Northwest Research Station. 18 p.

During the past 30 years, spruce forests of Alaska’s Kenai Peninsula have undergone dramatic changes resulting from widespread spruce bark beetle

(Dendroctonus rufipennis (Kirby)) infestation. In 1987 and again in 2000, the

Pacific Northwest Research Station’s Forest Inventory and Analysis Program

conducted initial and remeasurement inventories to assess broad-scale impacts of

this infestation.

Changes in regeneration of Sitka spruce (Picea sitchensis (Bong.) Carr.) and

white spruce (Picea glauca (Moench) Voss) are examined by using data collected

on 130 plots. Regeneration of Sitka and white spruce in terms of mean number of

seedlings per plot is not significantly different from the 1987 findings. The number

of plots where seedling stocking remained at previous levels or increased, slightly

exceeded the number of locations where seedling stocking declined. Almost half

the plots (49 percent) had decreased numbers of seedlings, and almost 72 percent

of the plots fell in the less-than-fully-stocked category in both inventories. Also, the

distribution of the seedlings over the plot was not uniform. No plots had seedlings

on all plot cluster sample points in either inventory.

Keywords: Forest surveys, timber resources, reproduction (spruce), Alaska (Kenai

Peninsula).
Summary

Alaska’s Kenai Peninsula is ecologically and geographically diverse. Forest cover

on the peninsula reflects that diversity. Resulting forest types range from those

similar to interior Alaska’s (white spruce [Picea glauca (Moench) Voss], black

spruce [P. mariana (Mill.) B.S.P.], and paper birch [Betula papyrifera Marsh]) to

those common in the mountainous south-coastal regions (Sitka spruce [Picea

sitchensis (Bong.) Carr.] and mountain hemlock [Tsuga mertensiana (Bong.)

Carr.]).

During the past three decades, populations of the spruce beetle (Dendroctonus

rufipennis (Kirby)) reached epidemic proportions; the scale of the infestation has

declined dramatically in recent years. Interest has risen on the impacts of the beetle

infestation, particularly as regards its effect on future forest composition. This

study examined data collected by the Pacific Northwest Research Station, Forest

Inventory and Analysis Program in 1987 and again in 2000 to assess impacts of the

infestation on spruce reproduction dynamics.

Spruce seedling data were examined to assess seedling stocking in 1987 and

2000 to identify regional patterns of differences. Analysis indicates that seedling

stocking conditions in 2000 differ little from those found in 1987. Across all study

plots there is no general decline or increase in seedling stocking. The number of

plots where seedling stocking remained at previous levels, or increased, slightly

exceeded the number of locations where seedling stocking declined. Seedling

stocking on almost half the study plots is likely below levels needed to provide

relatively rapid, short-term regeneration of fully stocked, mature spruce stands.
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

1

Introduction

This study provides a broad view of spruce reproduction dynamics in south-central

Alaska’s Kenai Peninsula. The region is between 148o

30’ and 152o00’ W. longitude

and between 59o

05’ and 61o05’ N. latitude (fig. 1). The area is about 5.2 million

acres, and forest land accounts for about 1.9 million acres (van Hees and Larson

1991). For several decades, the forest resource–white spruce (Picea glauca

(Moench) Voss), Sitka spruce (P. sitchensis (Bong.) Carr.), and Lutz spruce

(P. x lutzii Little), in particular–has been damaged owing to an infestation of the

spruce beetle (Dendroctonus rufipennis (Kirby)).

The Pacific Northwest Research Station, Forest Inventory and Analysis (FIA)

Program conducted an inventory in 1987 to assess impacts of the infestation. The

FIA Program remeasured the plots in 2000. Analysis of the 1987 inventory data

indicated that the infestation in 1987 was larger than in the recent past and that it

would maintain its magnitude and then likely increase in the near future (van Hees

1992.) The infestation did expand to all forests with white and Sitka spruce, but by

2000, when remeasurement began, spruce beetle populations had declined dramatically (fig. 2) Annual aerial surveys indicated populations had fallen to endemic

levels in many areas where they recently had been considered epidemic, and by

Figure 1—Kenai Peninsula forest inventory unit.
RESEARCH PAPER PNW-RP-563

2

2002 the epidemic was essentially over (Wittwer 2003). This study addresses two

questions: How did the 2000 spruce reproduction status differ from that found in

1987, and what regional differences exist?

The Kenai Peninsula is ecologically diverse; three ecoregions are found there

(fig. 3) The Cook Inlet Basin is characterized by a mild climate, level to rolling

topography, and soil generally free from permafrost. Vegetation includes black

spruce (Picea mariana (Mill.) B.S.P.) forests, ericaceous shrubs in open bogs,

mixed forests of white and Sitka spruce, quaking aspen (Populous tremuloides

Michx.), and birch (Betula papyrifera Marsh.) on better drained sites, and tallshrub communities of willow (Salix spp.) and alder (Alnus spp.) on slopes along

the periphery of the basin. Conversely, the Chugach–St. Elias Mountains region has

steep and rugged topography, a transitional climate, and is largely barren of vegetation other than dwarf and low-scrub communities. Along valley bottoms and lower

valley slopes, alder shrublands and mixed forests are present. The Gulf of Alaska

Figure 2—Sequential maps showing spruce beetle (SPB) activity on the Kenai Peninsula, 1983–2000 (Wittwer 2004).

Spruce beetle mortality

Prior SPB mortality

Nonaffected forest

Nonforest

Glacier
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

3

coast region is characterized by deep narrow bays, steep valley walls, and irregular

coastlines with glacial moraine deposits on lower slopes. The climate is maritime,

and forests of Sitka spruce and mountain hemlock (Tsuga mertensiana (Bong.)

Carr.) are found near sea level (Nowacki and others 2001).

Forest-type distribution on the Kenai Peninsula (fig. 4) is closely aligned with

ecoregions described above. White and black spruce, paper birch, and quaking

aspen are generally found in the Cook Inlet Basin, Sitka spruce in the Gulf- of

Alaska Fjordlands, and mountain hemlock in the Chugach–St. Elias Mountains

region. A few plots with cottonwood (P. trichocarpa Torr. & Gray) are also found

in the Chugach–St. Elias Mountains region.

Spruce regeneration dynamics is of particular concern where spruce mortality

was highest. Spruce mortality over the last decade follows regional forest-type

patterns: generally declining mortality in northwestern regions where spruce was a

secondary forest component versus generally increased mortality where spruce

stands predominate, particularly western and southwestern regions of the peninsula

(fig. 5).

Figure 3—Ecoregions of the Kenai

Peninsula, Alaska (Map by Dustin

Wittwer).
RESEARCH PAPER PNW-RP-563

4

Figure 4—Inventory plots by forest type, Kenai Peninsula, Alaska, 2000.

Sitka spruce

White spruce

Mountain hemlock

Paper birch

Quaking aspen

Cottonwood

Black spruce

Forest types Forest types

White spruce

Sitka spruce

Black spruce

Mountain hemlock

Paper birch

Quaking aspen

Cottonwood
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

5

Methods

The inventory design used a double sample for stratification to improve area

estimation (Bickford 1952). In the first sample, 5,597 photopoints were systematically distributed over 1:60,000-scale aerial photographs and then interpreted. Each

photopoint was placed in one of four strata: productive forest (forest land capable

of producing at least 20 cubic feet of wood per acre per year at culmination of

mean annual increment), other forest, nonforest, and water. Forest land is land at

least 10-percent stocked by live trees of any size, or land formerly having such tree

cover and not currently developed for nonforest use. The minimum area for classification as forest land or subclasses of forest land was 1 acre.

From the 5,597 photopoints, a random sample of 1,216 plots was selected for

potential ground visitation. All potentially productive forest-land plots (n = 130)

were selected for ground measurement. These ground plots were initially measured

Figure 5—Inventory plots showing increased or decreased spruce mortality from 1987 to 2000,

Kenai Peninsula, Alaska.

Mortality higher in 2000

Mortality lower in 2000 Mortality lower in 2000

Mortality higher in 2000
RESEARCH PAPER PNW-RP-563

6

in 1987 and were remeasured in 2000. Ground plots were sampled with a five-point

cluster (a central point with four additional points located 328.1 feet away in each

cardinal direction).

Initial installation of the plot in 1987 required crews to locate the plot with

respect to enduring reference points recognizable on aerial photos and the ground

to aid future relocation of the plot in the event of fire, timber cutting, or other

changes making visual relocation difficult. Some plot or point monumentation

could not be recovered in 2000. In such cases, the plot (or part of plot) was reinstalled at the same location. Distance and azimuth data collected in 1987 were

used in 2000 to ensure crews installed replacement points or plots in the correct

location.

Variable-radius sampling was used to select trees. Measurements taken on

these trees were used to estimate plot characteristics such as stand-size class, forest

type, and volumes per acre. Total numbers of seedlings by species, on a 4.9-footradius microplot centered on each point in the cluster, were recorded. Seedlings

were recorded only if they were established seedlings. A tree was considered an

established seedling if it was less than 1.0 inch in diameter at breast height, had

good coloration, no evidence of disease, and a root system in contact with mineral

soil. Data-collection procedures are described in USDA Forest Service documents

(1987, 2000.)

Plots that had at least one spruce seedling (either Sitka, white, or Lutz spruce)

in either inventory were selected for this analysis. Ninety-six plots met this criterion. Plots without spruce seedlings in either inventory were considered as not

contributing to spruce reproduction dynamics. T – tests (Snedecor and Cochran

1967) were performed on all 130 plots and on the 96-plot subset to examine overall

mean differences in numbers of seedlings per plot between the two inventories.

In south-central Alaska, Sitka and white spruce cross-pollinate to produce the

hybrid Lutz spruce. Identification of Lutz spruce from features apparent to the

unaided eye is difficult. Field crews were instructed to identify trees as either white

spruce or Sitka spruce depending on which species the tree most closely resembled.

Spruce seedling stocking on each plot was calculated as the sum of the numbers of spruce seedlings found on all five microplots within that plot. To assess

magnitude of changes in spruce seedling stocking, plots were grouped into four

levels of spruce seedling stocking. The minimum stocking levels were (1) no

seedlings in one inventory, (2) one or two seedlings in either inventory, (3) three

to four seedlings in either inventory, and (4) five or more seedlings in either

inventory. All 96 plots were used for each group. Under the sampling scheme

used for the initial and remeasurement inventories, each seedling sampled
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

7

represents about 100 seedlings per acre. Plots with five or more seedlings are

considered fully stocked.

Decades of spruce-beetle-caused mortality brought about changes in stand-size

class. Spruce reproduction in areas of high mortality, as reflected in stand-size class

decreases, was characterized by examining seedling stocking dynamics in relation

to regional changes in plot stand-size class. Plot stand-size class was calculated by

using stocking of live, growing-stock trees (USDA Forest Service 2003.) Growingstock trees include all live trees except for cull trees.

Results

Appendix table 6 lists study plots with stand-size class and number of seedlings at

both measurement dates. Not all remeasurement points were in exactly the same

locations because monumentation placed in 1987 was not recovered (app. table 6.)

Five plots were completely reinstalled, one required reinstallation of four points in

the cluster, six needed two points reinstalled, and nine had one point needing

reinstallation.

No significant difference is evident in the mean number of seedlings per plot

across the inventory unit between 1987 and 2000 (table 1).

Stand-Size Class Dynamics

Plot stand-size classes declined between 1987 and 2000. Forty-two percent (40

plots) of all plots showed stand-size reduction. Sixty plots had sawtimber-sized

stands in 1987. Stand-size class declined on 34 (57 percent) of these plots; 45

percent became nonstocked (table 2.) Reduction of stand-size class from sawtimber

to nonstocked indicates near to total mortality of all spruce trees on the plot.

Generally, in regions of increased spruce mortality (fig. 5), stand-size class declined between 1987 and 2000, whereas in regions of lower mortality, stand-size

class was more stable (fig. 6).

Seedling Stocking Dynamics

There is little indication of significant increases or decreases in seedling stocking

across all plots (fig. 7). Almost half of the plots (47) had decreased numbers of

seedlings, 37 had increases, and on 12 plots, seedling stocking remained level.

Fifty-one percent (49 plots) of all plots were stocked with at least one seedling

in both inventories (table 3). Twenty-five plots (26 percent) were not stocked with

any seedlings in 1987 but had 1 or more seedlings by 2000. Twenty-two plots were

stocked with at least one seedling in 1987 but by 2000 had no seedlings on them.

Twenty-eight percent (27 plots) of all plots were at least fully stocked (5 or more
RESEARCH PAPER PNW-RP-563

8

Table 1—Results of t-tests comparing 1987 and 2000 mean number of

seedlings per plot for all plots (df = 129) and for only those plots with

spruce seedlings on either occasion (df = 95)

Degrees t Critical

Survey date Mean of freedom alpha value value

1987 2.8307 129 0.05 0.5057 1.9797

2000 2.5304

1987 3.8333 95 .05 .5052 1.9883

2000 3.4375

Table 2—Number of plots, with at least one spruce seedling at either or both inventories, by stand-size class, Kenai Peninsula, Alaska, 1987 and 2000

Stand-size class, 2000

Stand-size Seedling All

class, 1987 Nonstocked and sapling Poletimber Sawtimber classes

Number of plots

Nonstocked 2 — — — 2

Seedling and

sapling 1 2 2 — 5

Poletimber 3 2 17 7 29

Sawtimber 27 2 5 26 60

Total 33 6 24 33 96

— = no data collected.
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

9

Figure 6—Inventory plots by stand-size class change from 1987 to 2000, Kenai Peninsula, Alaska.

5 1 

Stand-size class change 

Decline

No decline

Stand-size class change

No decline

Decline
RESEARCH PAPER PNW-RP-563

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seedlings) in at least one inventory. Ten were fully stocked at both inventories, nine

that were not fully stocked in 1987 became so in 2000, and eight that were fully

stocked in 1987 were less than fully stocked in 2000.

Among marginally well-stocked plots (at least three seedlings per plot), only

slightly more than half (57 percent or 55 plots) of the plots were stocked in at least

one inventory (table 3). Eighteen plots were stocked in 1987 and 2000, stocking

Figure 7—Individual plot changes in number of spruce seedlings and stand-size class, Kenai Peninsula, Alaska, 1987 to 2000.

Table 3—Number of plots by seedling stocking level, Kenai Peninsula, Alaska,

1987 to 2000

Seedling stocking level, 2000

Seedling stocking

level, 1987 0 1–2 3–4 5 + Total

Number of plots

0 14 3 8 25

1–2 16 11 7 0 34

3–4 3 10 5 1 19

5 + 3 3 2 10 18

Total 22 38 17 19 96

-50

-40

-30

-20

-10

0

10

20

30

40

50

1 9 7

Plot

Number of seedlings

Stand-size class declined

Stand-size class did not decline
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

11

rose to three or more seedlings between 1987 and 2000 on 18 plots, and on 19

plots, the 1987 stocking declined to less than three seedlings by 2000.

Few plots were fully stocked (five or more seedlings) in either inventory (app.

table 6). Almost 72 percent of plots fall in the less-than-fully-stocked category in

both inventories. Although a plot is considered fully stocked by the presence of five

or more seedlings, the spatial distribution of the seedlings over the five sample

points on the plot is rarely uniform. No plots had seedlings on all five points at

either inventory.

Regional differences in spruce reproduction dynamics are evident. In the northwestern areas of the inventory unit where mortality declined, stand-size class

did not decline, and paper birch forest types predominate, reproduction dynamics

were relatively static (fig. 8). Most locations with one or more seedlings in 1987

remained stocked with at least one seedling (61 percent), 25 percent showed

improvement from no seedlings to at least one, and 14 percent declined from one

or more seedlings to not stocked (table 4).

Spruce reproduction in the southwestern region was more dynamic (fig. 9).

The forests of this region are mainly composed of spruce types and suffered extensive mortality with resultant declines in stand-size class. Forty-two percent of the

Stocking improved 

No change

Stocking declined 

Seedling stocking dynamic 

Figure 8—Inventory plots by spruce seedling

stocking dynamic where stand-size class did

not decline, Kenai Peninsula, Alaska, 1987 to

2000.

Stocking improved

No change

Stocking decline

Seedling stocking dynamic
RESEARCH PAPER PNW-RP-563

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Table 4—Number of plots by seedling stocking level for plots where standsize class did not decline after 1987, Kenai Peninsula, Alaska

Seedling stocking level, 2000

Seedling stocking

level, 1987 0 1–2 3–4 5 + Total

Number of plots

0 8 1 5 14

1–2 6 8 4 0 18

3–4 2 5 5 0 12

5 + 0 3 2 7 12

Total 8 24 12 12 56

Stocking improved 

No change

Stocking declined 

Seedling stocking dynamic Seedling stocking dynamic

Stocking improved

No change

Stocking decline

Figure 9—Inventory plots by spruce seedling stocking dynamic where stand-size class declined between

1987 and 2000, Kenai Peninsula, Alaska.
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

13

plots where stand-size class declined maintained spruce seedling stocking levels

of at least one seedling; 26 percent showed stocking levels improved from no

seedlings in 1987 to at least one seedling, and on 33 percent, stocking declined to

zero (table 5).

Discussion

The status of spruce reproduction on productive forest land in 2000 was not

dramatically different from that found in 1987. Most plots did not have full stocking at either inventory. In 1987, the spruce forests were mature (63 percent of plots

had sawtimber-sized stands); by 2000, many of these locations had become

nonstocked, having no trees at least 5 inches in diameter. Similarly, Holsten et al.

(1995) in a study conducted near Hope, Alaska, in the Resurrection Creek drainage

of the north-central Kenai Peninsula to examine effects of fire and the spruce beetle

outbreak noted spruce seedling density was low at both the beginning (1980) and

end (1991) of the study. Revisits of these plots in 1996 (Schulz 2000) found more

of the unburned plots had spruce seedlings than did the burned plots.

The survey protocol used to count seedlings for this study likely underestimates number of seedlings. The requirement that a seedling be established with

roots in mineral soil can cause undercounts. White spruce can reproduce under the

closed canopy of mature stands, and seed germination occurs on a variety of

seedbeds–commonly on rotted logs. On the southern peninsula, where stands have

usually not burned for hundreds of years according to radiocarbon-dated soil

charcoal, most tree recruitment is on nurse logs and nurse stumps (Berg 2004.)

Between 1987 and 2000, logging activity affected about 29 percent of the plots.

Nine plots were clearcut either entirely or partially: two were entirely cut, one was

Table 5—Number of plots by seedling stocking level for plots where standsize class declined between 1987 and 2000, Kenai Peninsula, Alaska

Seedling stocking level, 2000

Seedling stocking

level, 1987 0 1–2 3–4 5 + Total

Number of plots

0 6 2 3 11

1–2 10 3 3 0 16

3–4 1 5 0 1 7

5 + 3 0 0 3 6

Total 14 14 5 7 40
RESEARCH PAPER PNW-RP-563

14

80 percent cut, three were 40 percent cut, and three were 20 percent cut. Additionally, 19 other plots had some harvest effect (> 25 percent of trees cut or damaged in

association with tree removals.) Reproduction after stand removal (either through

natural agents or by mechanical means) can occur on remaining organic material

and exposed mineral soil, but seedling-to-seed ratios drop as subsequent growth

of nontree vegetation increases with successive years (Burns and Honkala 1990:

211-212).

Stocking of five seedlings per plot is considered a fully stocked location; this

translates to about 550 seedlings per acre. Stocking by one seedling per plot cannot

be considered good stocking. Twenty-three plots were stocked with one seedling in

1987, and 11 more had two seedlings. In 2000, the numbers of plots with one and

two seedlings were 22 and 16, respectively. In 1987 there were 18 plots that had

five or more seedlings, and in 2000 the number was 19 (app. table 6.) In general,

although there were changes on individual plots, seedling stocking status did not

change dramatically between 1987 and 2000.

Regional differences coincident with ecoregion and forest type distributions

exist. There are few pure spruce stands in the northwest or east; spruce mortality

was highest in southwest along with stand-size declines where most of the spruce

mortality occurred. However, regeneration is taking place–sometimes at relatively

high levels, such as along the southern edge of the lowlands region.

Metric Equivalents

1 inch = 2.54 centimeters

1 foot = 0.3048 meter

1 mile = 1.609 kilometers

1 acre = 0.4047 hectare

1 cubic foot = 0.0283 cubic meter

1 cubic foot per acre = 0.07 cubic meter per hectare

Degrees Fahrenheit = (1.8 °Celsius) + 32

References

Berg, E. 2004. Personal communication. Ecologist, U.S. Fish and Wildlife Service,

Kenai National Wildlife Refuge, P.O. Box 2139, Soldotna, Alaska 99669.

Bickford, C.A. 1952. The sampling design used in the forest survey of the Northeast. Journal of Forestry. 50(5): 290-293.

Burns, R.M.; Honkala, B.H., tech. coords. 1990. Silvics of North America: 1.

Conifers. Agric. Handb. 654. Washington, DC: U.S. Department of Agriculture,

Forest Service. 675 p. Vol. 1.
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

15

Holsten, E.H.; Werner, R.A.; DeVelice, R.L. 1995. Effects of a spruce beetle

(Coleoptera: Scolytidae) outbreak and fire on Lutz spruce in Alaska. Environmental Entomology. 24(6): 1539-1547.

Nowacki, G.J.; Spencer, P.; Brock, T.; Fleming, M.; Jorgenson, T. 2001.

Unified ecoregions of Alaska and neighboring territories. U.S. Geological

Survey Map. Open-file Report 02-297. [Place of publication unknown]: U.S.

Geological Survey.

Schulz, B.K. 2000. Resurrection Creek permanent plots revisited. Tech. Rep. R10-

TP-89. Anchorage, AK: U.S. Department of Agriculture, Forest Service, Forest

Health Protection, State and Private Forestry. 14 p.

Snedecor, G.W.; Cochran, W.G. 1967. Statistical methods. 6th ed. Ames, IA: Iowa

State University Press. 593 p.

U.S. Department of Agriculture, Forest Service. 1987. Field procedures for the

1987 Kenai bark beetle inventory, Kenai Peninsula, Alaska. Anchorage, AK:

U.S. Department of Agriculture, Forest Service, Pacific Northwest Research

Station. 100 p.

U.S. Department of Agriculture, Forest Service. 2000. Field procedures for the

Kenai spruce bark beetle inventory, 2000. Anchorage, AK: U.S. Department of

Agriculture, Forest Service, Pacific Northwest Research Station. 149 p.

U.S. Department of Agriculture, Forest Service. 2003. Algorithms for calculation of stand-size class for the Kenai Bark Beetle inventory. Unpublished

document. On file with: Forestry Sciences Laboratory, 3301 C Street, Suite

200, Anchorage, AK 99503.

van Hees, W.W.S. 1992. An analytical method to assess spruce beetle impacts on

white spruce resources, Kenai Peninsula, Alaska. Res. Pap. PNW-RP-446.

Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 15 p.

van Hees, W.W.S.; Larson, F.R. 1991. Timberland resources of the Kenai Peninsula, Alaska, 1987. Resour. Bull. PNW-RB-180. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 56 p.

Wittwer, D., comp. 2003. Forest insect and disease conditions in Alaska–2002.

Tech. Rep. R10-TP-113. Juneau, AK: U.S. Department of Agriculture, Forest

Service, Alaska Region. 62 p.

Wittwer, D. 2004. Personal communication. Aerial survey lead, Forest Health

Protection, U.S. Department of Agriculture, Forest Service, Alaska Region,

2770 Sherwood Lane, Suite 2A, Juneau, AK 99801.
RESEARCH PAPER PNW-RP-563

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Appendix

Table 6—Study plots by number of new points installed, stand-size class, and number

of spruce seedlings, 1987 and 2000, Kenai Peninsula, Alaska

Number of spruce

seedlings

Stand-size class (No. of points/plot)

Number of

Plot new points

number installed 1987 2000 1987 2000

1 0 Sawtimber Sawtimber 4(2) 1(1)

2 0 Sawtimber Nonstocked 8(1) 0

3 1 Sawtimber Sawtimber 0 8(2)

20 0 Sawtimber Nonstocked 0 1(1)

22 0 Poletimber Nonstocked 2(2) 0

23 2 Nonstocked Nonstocked 0 18(1)

24 0 Sawtimber Nonstocked 2(2) 2(1)

26 0 Poletimber Poletimber 4(2) 0

28 0 Poletimber Poletimber 2(2) 1(1)

29 0 Poletimber Sawtimber 9(2) 9(3)

30 0 Poletimber Seedling/sapling 9(2) 8(2)

31 2 Sawtimber Nonstocked 0 1(1)

32 0 Poletimber Poletimber 1(1) 1(1)

33 1 Sawtimber Nonstocked 0 2(1)

35 0 Seedling/sapling Seedling/sapling 24(4) 19(3)

37 2 Poletimber Poletimber 0 1(1)

39 0 Poletimber Poletimber 8(4) 4(3)

40 2 Seedling/sapling Seedling/sapling 2(1) 0

42 0 Poletimber Seedling/sapling 4(2) 1(1)

43 0 Sawtimber Poletimber 7(3) 5(3)

44 0 Sawtimber Sawtimber 3(1) 2(1)

47 0 Sawtimber Sawtimber 0 2(2)

48 0 Poletimber Poletimber 7(4) 2(1)

49 0 Sawtimber Sawtimber 1(1) 1(1)

50 0 Poletimber Poletimber 3(2) 3(2)

51 0 Sawtimber Sawtimber 4(1) 3(1)

52 0 Poletimber Sawtimber 3(1) 0

53 1 Sawtimber Sawtimber 1(1) 0

56 0 Poletimber Poletimber 7(1) 2(2)

57 0 Poletimber Sawtimber 1(1) 1(1)

58 0 Poletimber Poletimber 4(1) 4(1)

59 1 Sawtimber Sawtimber 1(1) 0

60 0 Poletimber Poletimber 0 2(2)

62 0 Sawtimber Sawtimber 1(1) 0

64 0 Poletimber Sawtimber 0 1(1)

66 0 Poletimber Poletimber 29(3) 15(3)

67 0 Poletimber Nonstocked 2(2) 0

68 0 Sawtimber Sawtimber 1(1) 1(1)
Spruce Reproduction Dynamics on Alaska’s Kenai Peninsula, 1987-2000

17

Table 6—Study plots by number of new points installed, stand-size class, and number

of spruce seedlings, 1987 and 2000, Kenai Peninsula, Alaska (continued)

Number of spruce

seedlings

Stand-size class (No. of points/plot)

Number of

Plot new points

number installed 1987 2000 1987 2000

70 0 Sawtimber Sawtimber 2(1) 2(1)

71 0 Poletimber Sawtimber 1(1) 3(1)

72 0 Sawtimber Sawtimber 4(2) 2(2)

73 1 Sawtimber Nonstocked 10(2) 0

74 5 Sawtimber Nonstocked 2(1) 0

75 1 Sawtimber Sawtimber 1(1) 4(2)

76 0 Sawtimber Sawtimber 7(1) 4(1)

77 0 Sawtimber Sawtimber 8(1) 6(3)

78 5 Sawtimber Nonstocked 0 1(1)

79 5 Poletimber Nonstocked 0 7(4)

80 0 Sawtimber Nonstocked 2(1) 0

81 0 Sawtimber Poletimber 1(1) 0

82 0 Sawtimber Nonstocked 2(2) 0

83 0 Sawtimber Nonstocked 1(1) 0

84 0 Sawtimber Seedling/sapling 0 3(1)

85 0 Sawtimber Nonstocked 3(1) 1(1)

86 4 Sawtimber Nonstocked 1(1) 0

88 1 Sawtimber Nonstocked 1(1) 0

89 1 Sawtimber Nonstocked 1(1) 0

90 0 Sawtimber Nonstocked 1(1) 3(2)

91 0 Sawtimber Nonstocked 1(1) 2(1)

92 0 Sawtimber Nonstocked 3(1) 1(1)

93 2 Sawtimber Nonstocked 0 7(1)

95 0 Sawtimber Poletimber 0 37(1)

96 0 Sawtimber Sawtimber 3(1) 4(1)

97 0 Sawtimber Nonstocked 3(2) 2(1)

98 1 Sawtimber Nonstocked 0 3(1)

101 0 Sawtimber Nonstocked 1(1) 3(1)

104 0 Sawtimber Nonstocked 1(1) 3(1)

106 0 Sawtimber Seedling/sapling 11(1) 11(3)

107 0 Sawtimber Sawtimber 1(1) 3(2)

108 0 Sawtimber Nonstocked 4(1) 7(1)

110 0 Sawtimber Nonstocked 0 1(1)

111 0 Sawtimber Sawtimber 0 24(2)

113 0 Sawtimber Sawtimber 0 4(3)

114 0 Sawtimber Sawtimber 3(2) 1(1)

115 0 Poletimber Poletimber 15(4) 2(1)

116 0 Sawtimber Sawtimber 1(1) 2(1)

118 0 Sawtimber Sawtimber 0 1(1)
RESEARCH PAPER PNW-RP-563

18

Table 6—Study plots by number of new points installed, stand-size class, and number

of spruce seedlings, 1987 and 2000, Kenai Peninsula, Alaska (continued)

Number of spruce

seedlings

Stand-size class (No. of points/plot)

Number of

Plot new points

number installed 1987 2000 1987 2000

119 0 Poletimber Poletimber 1(1) 0

120 0 Seedling/sapling Poletimber 10(3) 5(2)

121 0 Poletimber Poletimber 4(2) 4(2)

123 0 Poletimber Sawtimber 17(2) 6(2)

125 0 Sawtimber Sawtimber 0 7(1)

126 0 Sawtimber Nonstocked 3(2) 0

127 0 Sawtimber Poletimber 1(1) 2(2)

128 0 Sawtimber Sawtimber 2(2) 2(2)

129 0 Poletimber Poletimber 27(4) 12(1)

130 0 Poletimber Sawtimber 0 1(1)

134 0 Sawtimber Nonstocked 4(2) 1(1)

136 0 Sawtimber Sawtimber 0 7(2)

137 5 Seedling/sapling Nonstocked 43(4) 0

138 0 Poletimber Poletimber 4(2) 1(1)

139 2 Nonstocked Nonstocked 1(1) 0

140 0 Sawtimber Poletimber 0 2(1)

142 0 Seedling/sapling Poletimber 2(1) 3(2)

143 0 Poletimber Poletimber 0 1(1)

144 0 Sawtimber Sawtimber 0 1(1)
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