State of Alaska – Division of Forestry
Spatial Analysis Project
March 2007
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Table of Contents
Page
Executive Summary
3
Introduction
4
Alaska Forest Resources
4
Forest Stewardship Program in Alaska
5
State Specific Methodology
7
Literature Cited
10
Spatial Analysis Tables
11
Alaska SAP Layers
Prior Timber Harvest
` Fire Management Zones
Priority Watersheds
Forest Pests
Proximity to Transportation
Population Density
Forest Legacy Area
Fire History
12
13
14
15
16
17
18
19
SAP Value by Acres for Prioritization
20
Modeling Flow Chart
21
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Executive Summary
The Alaska Division of Forestry requested to be an early participant in developing
a Spatial Analysis Project for the Forest Stewardship Program. Alaska provides a
contrast to other states in size, ownership pattern, population density, and resource
issues.
The 11 natural resource GIS data layers selected by the Northeast states were
developed for Alaska, with some modifications due to scale and available
information. Layers for private forest land and Forest Stewardship landowners
were also prepared. The 11 resource layers were presented to the Alaska Forest
Stewardship Committee for weighting. Of these, the committee considered 7 to be
little value for prioritization in Alaska. The committee requested 4 additional
resources data layers. The committee then ranked the final 8 data layers for
importance. This ranking allowed prioritization of private forest lands as high,
medium, and low, with approximately 1/3 of the area in each category. Most land
rated as high priority was due to the two highest priority resource issues, past
timber harvest and wildfire protection level. Roughly 16% of potential private
forestland has a Forest Stewardship plan, and about 22% of high priority land has a
Forest Stewardship plan.
During 2005, contacts were attempted with all Alaska Forest Stewardship Program
landowners to request information about implementation of Forest Stewardship
plans. Responses were mixed, although a majority indicated some activity
connected to the plan. All participating landowners were entered into a
standardized database which was linked to the GIS prioritization.
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Introduction
The Alaska Division of Forestry mission is to develop, conserve, and enhance
Alaska’s forests to supply a sustainable supply of forest resources for Alaskans.
This mission encompasses both public and private forestland. The Alaska Forest
Resources and Practices Act, the Fire and Aviation Program, the Forest Health
Protection Program, and the Forest Stewardship Program all address private
forestland.
The Spatial Analysis Project (SAP) is a nation-wide effort to apply geographic
information systems (GIS) technology to private forestlands with emphasis on the
Forest Stewardship Program. The objectives are to promote strategic program
delivery, improve program accountability, and provide a consistent way to assess
the impact of Forest Stewardship plans.
This report contains the results of the first SAP application for Alaska. As with all
GIS applications, the job is never complete. Some GIS data layers need better
information than currently available, such as timber harvest areas. The selection of
priority resources, the ranking, and importance should be re-examined periodically.
The amount of land assigned to high, medium, and low priorities can be adjusted to
be aligned with national standards. New additions and updates to the landowner
database needs to occur regularly.
Alaska Forest Resources
Alaska encompasses a diverse set of geological, climatic, and vegetative
conditions. The state’s 365 million acres has been divided into six ecological
units: Southeast, Southcentral, Southwest, Interior, Northwest, and Arctic (Viereck
and others 1992). Forest resources are often divided into two regions: Coastal and
Boreal (see title page).
There are 126 million acres of forest land in Alaska. This is 35 percent of the
state’s total area. There are 11 million acres of coastal, or maritime, forest and 115
million acres of interior or boreal forest. More than two-thirds of Alaska’s
communities and more than three-quarters of the state’s population live in or
adjacent to these forests.
Alaska has the largest acreage of private forest lands of any state in United States
(Smith and others, 2004):
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Area
U.S.
Alaska
Alaska %
All
owners
748,922
126,869
17%
Total
National Other
State
federal forest
federal
246,425 148,456
97,696 63,140
90,994 10,455
52,968 27,469
37%
7%
54%
43%
Local Private
9,597 429,761
101 35,875
1%
8%
Information about forest land ownership Alaska is limited and changing. The most
recent national survey reported that Alaska has an estimated 16,600 private
landowners with one or more acres of forestland (Birch 1997). However, the
accuracy of this report is questionable, because only 9 million acres of private
forest land was reported, which is well below other reputable sources.
There are many physical and biological threats to private forest lands in Alaska.
Human intervention has been limited in most of Alaska’s forest land, and the
principle management activity has been wildfire suppression. Alaska’s predominate
old forest is susceptible to many natural disturbance agents, such as wildfire, insects,
disease, or windthrow. Some of Alaska’s forests are young, primarily due to recent
timber harvest or wildfire. Young forests can also be impacted by natural disturbance
agents, although delayed regeneration may be a more significant threat for forest
resources. Fish and wildlife components of forest resources may be threatened by
unrestricted timber harvest and road development, and Alaska’s Forest Resources
and Practices Act seeks to maintain fish and wildlife populations following timber
harvest. Human habitations and developments have become forest resource threats in
some locations, particularly near urban centers. The Forest Legacy Program is now
available in Alaska through Alaska State Parks and this may assist in reducing loss of
the most critical threatened forest. Invasive species have become a serious threat in
forests in other states. Although not yet a serious threat in Alaska, diligence in
prevention of invasive species is a recognized need. Global warming is apparent in
Alaska, and may become a serious forest resource threat.
Forest Stewardship Program in Alaska
Although settlement and development of Alaska is still limited compared to other
States, the potential for private forestlands in Alaska is great. The 1972 Alaska
Native Claims Settlement Act (ANCSA) provided 13 regional corporations and
over 200 village corporations entitlement to 44 million acres. ANCSA corporation
ownerships range from 10,000 acres for small villages to over 12 million acres for
regional corporations. Typical ANCSA village ownerships are 23,000 acres in
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southeast and 100,000 acres in interior. ANCSA Corporation lands mostly are near
traditional native villages, and thus are along major rivers or on marine bays and
inlets. Since forests are predominately on river floodplains or low elevation coastal
zones, many ANCSA corporations have forest resources. Approximately 2/3 of
ANCSA corporations have some forests, and approximately 1/2 of ANCSA
corporation lands meet federal standard for forestland.
The 1958 Statehood Act entitled the State of Alaska to receive 105 million acres,
and a significant amount of the Statehood entitlement has been transferred to
private owners. Individual land owners are concentrated along the road system.
Since most of Alaska is without roads, individual landowners are concentrated is
specific areas. The Boroughs of Matanuska-Susitna, Kenai Peninsula, and
Fairbanks North Star have the great majority of individual forest landowners.
Boroughs in Alaska are analogous to counties, but much larger. The Municipality
of Anchorage has approximately half of the state population, but this is urban or
suburban and mostly not suitable for Forest Stewardship. About half of Alaska has
no local government, and the State Legislature is the governing body. The area
without county government is termed the un-organized borough. Alaska has been
divided into Census Areas, but most do not correspond to local government entity.
By 2006, the Forest Stewardship Program has completed plans for 23 ANCSA
corporations and over 600 individual landowners in Alaska. Individual forest
landowners are concentrated in three areas in Alaska: Kenai Peninsula, Susitna
Valley, and Tanana Valley. The average individual ownership in the Forest
Stewardship Program is around 60 acres. The minimum acreage for the Forest
Stewardship Program in Alaska is generally 7 acres, but since 2005 ownerships
with a dwelling and 2 acres and more in a recognized wildland urban interface
(WUI) zone are eligible.
In the 1990’s Alaska’s Forest Stewardship Program had limited use of GIS
technology. A few ANCSA corporations had developed GIS maps and were used
in Forest Stewardship plans. By 2000, vegetation classification from Landsat
satellite imagery at 50-m resolution was available for about half of Alaska. This
resolution is usable for rural, large acreage ANCSA corporation planning where no
ground based vegetation assessment has been made. In the last several years, 1-m
resolution imagery has become available for the more populated portions of
Alaska. Hence, GIS technology is now indispensable for Forest Stewardship
Program. Therefore, applying the SAP to Alaska Forest Stewardship Program is a
logical progression.
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State Specific Methodology
The Alaska Division of Forestry was informed of this project in November 2003
and offered to be a pilot western state in December. Teleconferences were held in
December and January 2004 to discuss state proposals. Confirmation of acceptance
came in January 2004. A meeting between Northeast and Western pilot states and
State and Private Forestry personnel occurred in June 2004 in Seattle. At this
meeting, project expectations and timelines were discussed and examples from the
Northeast were presented. Alaska personnel described the Alaska situation,
including the need for different scales and resolutions for GIS products.
During the 2004 summer, computer and software upgrades were accomplished in
order to use the required Microsoft Access program for landowner data. Planning
and investigation of the best available GIS data sets was also begun. In October
2004, the project was introduced to the Alaska Forest Stewardship Committee.
Beginning in January 2005, Forest Stewardship staff began reviewing Forest
Stewardship plans and contacting landowners to request information about plan
implementation. This review included obtaining borough government property
identification codes, as assigned by the tax assessor’s office. Landowners were
contacted by letter or telephone or both. Many landowners responded with some
implementation information. Some landowners had sold their property, and some
had subdivided their property. Some landowners had no response. A few
landowners had died. When available, cost-share records were used to supplement
implementation data. Implementation did not always follow the Forest Stewardship
plan, particularly in areas affected by the rapidly moving spruce bark beetle
epidemic in the late 1990’s. Forest Stewardship plan recommendations may have
focused on monitoring for bark beetle and removing infested spruce, whereas
implementation was reforestation following salvage logging.
In May 2005 the project was again presented to the Forest Stewardship Committee,
and the need for determining additional data layers and prioritizing data layers was
described. In October 2005, completed maps of the 11 required resource data
layers were presented to the committee. At this time, the committee requested 4
new layers. These were: timber harvest within the last 30 years, proximity to
transportation including roads and navigable rivers, fire history, and forest legacy
area. Wildfire assessment was modified to fire management protection level, and
developing area was modified to population density. A weighting factor of zero
was assigned to 7 layers: slope, forest patch size, threatened and endangered
species, proximity to public lands, forested wetlands, public drinking water source,
and riparian buffer. The resulting 8 layers considered important in Alaska were
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ranked by the committee and given a weight based on their rank. The 8 layers (and
weights) are:
Prior Timber Harvest (22%)
Fire Management Zones (19%)
Presence of Insects or Disease (17%)
Priority Watersheds (14%)
Proximity to Transportation (11%)
Population Density (8%)
Forest Legacy Program (6%)
Fire History (3%).
The selection and ranking of the 8 layers was by the Forest Stewardship
Committee, but some rationale was evident from the committee discussion. Prior
Timber Harvest was considered important because these lands typically have ongoing management needs, such as reforestation, thinning, and road maintenance.
Fire Management Zones are areas given full or critical fires suppression
designation, and thus candidates for fuels treatment projects. Insect or Disease
importance reflects past impact of spruce bark beetle in south central Alaska, but
also concerns of other pests such as spruce bud worm, amber-marked birch leaf
miner, yellow-cedar decline, and spruce aphid. Priority watershed definition was
expanded to include miles of anadromous and resident high value fish streams and
this reflects importance of fish populations to Alaska. Proximity to Transportation
recognizes that much of Alaska has no transportation access and management
options are limited. Population density was selected as substitute for change in
households and thought a better characteristic for Alaska’s remote, rural nature.
Forest Legacy Areas was added to include parcels proposed for Legacy
acquisitions. Fire History is past fire events, which impact nearby communities but
often receive little post-fire management action.
Layers were weighted zero for a variety of reasons. Alaska has no listed threatened
or endangered species or candidate threatened or endangered species occurring in
forested habitats. Wildlife species of concern, such as neo-tropical migratory birds,
did not have useful available geographic datasets. Public lands are abundant in
Alaska, therefore proximity to public lands is not an important criteria.
Fragmentation and urban sprawl is only occurring in a small percentage of the
State, therefore forest patch size is not a significant issue. Although much of
Alaska is mountainous, most private forest lands are not mountainous and slope
has not been an important issue in forest planning thus far. Wetlands are extremely
abundant throughout Alaska and not a useful prioritization factor. Public drinking
water sources are few and watersheds contributing to drinking water are mostly
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public lands. Riparian zones are numerous and important in forest planning, but
length of fish streams was considered more important and with a better existing
dataset.
After selecting data layers, the Forest Stewardship Committee ranked the selected
layers from high to low. Then the committee assigned prioritization weighting
giving percentage base on ranking with equal spread between layers.
Following the committee assigning weight to each layer, the final GIS layers to
apply the weighting scheme were prepared. Each layer is represented in 250 meter
grid cell raster by a value equal to the weight of the layer assigned by the
committee. For example, if an individual cell was had Prior Timber Harvest (value
= 22) AND with in the 3 mile Proximity to Transportation (value = 11) distance,
and within no other layers, its resulting Suitability Value would be 22 + 11 = 33.
Using this additive modeling approach, the theoretical maximum value for an
individual grid cell is 100, the theoretical minimum is 0. The actual maximum
Suitability Value for the 20,770,604 acres of private forested land in Alaska is 97
(571 acres) and actual minimum is 0 (1,964,666 acres). Establishing High, Medium
and Low Suitability categories was set by assigning Suitability Values between 0
and 17 as Low (5,486,987 acres of private forest), between 18 and 32 as Medium
(6,412,646 acres of private forest), and between 33 and 97 to High (8,870,971
acres of private forest, see SAP values by acres on page 20).
Next the prioritization approach was applied to the 8 resource data layers (see
model flowchart page 21). The Analysis Mask of Private Land and Forested Land
is then applied to limit analysis to lands that qualify for Forest Stewardship
programs. In addition, a special mask consisting of the Alaska Ecoregions sub
regions Arctic Tundra/Brooks Foothills, Arctic Tundra/Beaufort Coastal Plain,
Arctic Tundra/Bering Sea Island and Maritime/Aleutian Islands was applied to
exclude all lands from those areas because of it is currently non-forested.
All landowners with Forest Stewardship plans were entered into SAP Access by
December 2005. All landowners were given a unique SAP code. SAP codes
included AK for Alaska, a location (IN for interior, MS for Mat-Su, KK for Kenai
Kodiak, SE for southeast, NC for Native Corporation), and a sequential number.
Plan recommendations were entered for nearly all landowners using the Forest
Service Activity Tracking System (FACTS) codes. Forest Stewardship plans were
not initially prepared expecting to someday codify recommendations or
implementation. Hence, some interpretation of plans and implementation was
needed to use the FACTS codes. Codes for new practices were requested and
approved by Northeast Area State and Private Forestry. New codes used for Alaska
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SAP were: 1282—Wildfire fuels reduction for defensible space, 8020—Forest
monitoring for damage from insects, disease, and weather, and 9003—Forest road
maintenance. Plans with change of owner were entered, but frequently no
implementation had occurred.
Existing GIS property coverage was obtained for most properties. The Bureau of
Land Management provided much of GIS coverage for Alaska Native
Corporations. Some native corporations provided separate coverage of their lands.
Borough governments provided digitized coverage of the tax parcel maps.
Landowner SAP identifier codes were matched with assessor property tax codes,
and then used to select Forest Stewardship parcels in the property GIS attribute
table. Many Stewardship plans cover multiple tax parcels. For a small number of
individual ownerships in the parts of Alaska lacking local government, a GIS
centroid identifies the property location.
Following completion of the SAP mapping and prioritization, the results were
presented to the Forest Stewardship committee in May 2006. The committee
accepted the results, but some clarification of data layers was requested.
Literature Cited
Birch, Thomas.W. 1997. Private Forest-land Owners of the Western United States,
1994. US Forest Service Resource Bulletin NE-137. 249 pgs.
Smith, Brad W., Patrick D. Miles, John S. Vissager, and Scott A. Pugh. Forest
Resources of the United States, 2002. US Forest Service General Technical Report
NC-241. April 2004. 146 pgs.
Viereck, L.A., C. T. Dyryness, A.R. Batten, and K.T. Wenzlick. 1992. The Alaska
Vegetation Classification. U.S. Forest Service General Technical Report PNWGTR-286. 278 pgs.
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Spatial Analysis Tables
1. Potential for Forest Stewardship Program Benefits and Existing Stewardship Plans.
Stewardship Capable Lands
Stewardship
Potential
Potential Forest
Non-Forest
Total
Acres
Percent Acres
Percent Acres
Percent
High
8,870,971
43% 8,298,823
57% 17,169,794
49%
Medium
Low
6,412,646
5,486,987
31% 2,564,673
26% 3,670,496
18% 8,977,319
25% 9,157,483
25%
26%
20,770,604
14,533,992
35,304,596
Total
2. Potential for Forest Stewardship Program Benefits and Existing Stewardship Plans.
Stewardship Potential
Low
Medium
High
Acres
Capable of
Stewardship
Stewardship
Plan (acres)
Stewardship
Plan vs.
Acres
Capable of
Stewardship
(%)
Total
9,157,483 8,977,319 17,169,794 35,304,596
602,551 1,011,404
6%
2,603,738 4,217,693
11%
15%
12%
3. Forest Stewardship Potential on Private Forest Lands and Existing Stewardship Plans.
Private Forest Lands Stewardship Potential
Private Forest Lands
Low
Medium
High
Total
Acres Capable of
Stewardship
5,486,987
6,412,646
8,870,971 20,770,604
Stewardship Plans
538,938
935,512
1,957,647 3,432,097
(acres)
Stewardship Plans
acres as % of
9%
14%
22%
16%
Private Forests
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