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Data Information and Reporting for Indicator E.a.
Oregon Indicator of Sustainable Forest Management E.a.
 
Composition, diversity, and structure of forest vegetation
 

Forestry Program for Oregon Strategy E:
Indicator E.a. is one of three indicators that will measure progress towards achieving Forestry Program for Oregon Strategy E: Contribute to the conservation of diverse native plant and animal populations and their habitats in Oregon's forests.
 
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Desired Trend
 
The composition, diversity, and structure of forest vegetation are within, or growing towards, desired future condition ranges established through the Oregon Conservation Strategy.

At-a-Glance: Condition, Trend, and Information
Once the data for the first report on this indicator has been reviewed and discussed by the Roundtable on Sustainable Forests, this section will display symbols that at-a-glance illustrate the condition, trend, and quality of information available for this indicator. 
Why is this indicator important?
A photo of a road through a thinning project in a northwest Oregon state forest
A thinning project in a northwest Oregon state forest
 
The composition and structure of vascular plants are important factors in assessing biological diversity of forested ecosystems.  Vegetation is the source of primary production and a primary determinant of habitat for many species. Changes in these factors due to non-native species are a particular concern at multiple spatial scales.  The composition and structure of plants can serve as indicators of changes to ecosystems, and as indicators of the status of other organisms and ecosystem processes that are difficult to measure directly.  Without these data, our ability to assess and evaluate changes in species composition, range shifts of native species as a result of climate change, or the spread of noxious and exotic plant species is greatly compromised.
 
 
Comparing differences in the composition and structure of plants assessed at different intervals of time can serve as indicators of changes to ecosystems, and as indicators of the status of other organisms and ecosystem processes that are difficult to measure directly. The information presented with this indicator is a first-in-time analysis and serves as a baseline from which future analyses can be compared. However, comparisons of the contemporary information represented here with historic inventories are problematic because of inconsistencies in the sampling designs between inventory periods and the fact that similar analyses for previous inventories have not yet been generated.  Changes in composition, structure, and forest canopy can be used to verify and relate information from this indicator to that presented in other indicators such as timber harvest rates, mortality from insects and diseases, amount of wildfire, conversion of forest land to other uses, carbon sequestration and storage, as well as the effects of climate change.  Detecting, quantifying, and accounting for changes also serves as an early warning and an informed basis for modifying forest policies as well as other policies that directly or indirectly affect forest ecosystems.  We are investigating the feasibility for including herbaceous and shrub species in future iterations of this indicator to track the status and trends of invasive species and those most sensitive to changes in climate.

 

What does this indicator tell us about sustainable forest management?
Condition:
The information provided by the first report for this indicator serves as a mid-scale assessment and relative index of forest conditions in terms of the composition and geographic distribution of plant species that comprise Oregon's forest ecosystems, the age and size structure of trees, and the percentage of land designated as forest covered by tree canopy.  These features can be used to quantify the dynamics of forest ecosystems from this point forward, given the forest inventory system is consistent through time.  The available data indicate that Oregon's forests remain dominated by the same native forest species that were present before European settlement.  Oregon lacks a statewide, all land use, native plant and animal conservation policy that current forest vegetation species abundance, spatial distribution, size class distribution, and canopy cover conditions can be measured against.
 

Trend:
The abundance, spatial distribution, size class distribution, and canopy cover ranges for these native species are highly diverse and likely are constantly changing over time - in some cases, significantly - due to forest management, insects, diseases, fire frequency and intensity, other natural disturbances, and ecological succession.  There is recent widespread mortality in the pine-dominated forests of central Oregon, various pathogens affecting other areas (ODF-USDA, 2009), research showing significant mortality in older forests in the western United States (Van Mantgem, et. al, 2009), and ongoing harvest, reforestation, and management of forest stands.  However, comparisons of the contemporary information represented here with historic inventories are problematic because of inconsistencies of sampling designs between inventory periods and the fact that similar analyses for previous inventories have not yet been generated.  Oregon also lacks a statewide, all land use, native plant and animal conservation policy that current forest vegetation species abundance, spatial distribution, site class distribution, and canopy cover trends can be measured against. 
 

Information:
The source of information for this indicator originated with the Forest Inventory and Analysis (FIA) program and the Continuous Vegetation Survey within the USDA Forest Service and the Bureau of Land Management.  The FIA program is implemented across all forestlands of the United States.  In Oregon, the FIA program collects tree mensuration information from a series of permanent field plots, compiles the data, and makes it available in databases and a variety of research reports.  The FIA plot-level data was integrated with satellite imagery in a multivariate statistical framework, commonly referred to as Gradient Nearest Neighbor (GNN) to impute measured forest conditions to all of Oregon's forested landscapes.  A small proportion of the GNN data was organized and used to inform this indicator.  The forest data collection system and the subsequent GNN analysis represent the state-of-the-art and significant investment in time and resources.  The only current data limitation is the lack of a time series of data.
 

Focus of Indicator E.a. and the Questions to be Answered
 
This indicator focuses on the structure and composition of vegetation comprising Oregon’s forests.  The information is rich in species-level information and can be used to answer questions such as: 
  • What are the plant species found in a sample of Oregon’s forests?
  • What is the actual rate of change in the spatial extent and abundance of individiual species forecast to occur with climate change?
  • How does the diversity and composition of plant species vary across Oregon’s forested landscape?
  • What is the relationship between plant diversity, canopy cover, and forest community?
  • What percentage of forest sampling sites contain invasive species?
 
The specific reports for this indicator focus on 1) diversity of forest plant species and, 2) the structure of forest vegetation including canopy cover and average tree size. This indicator provides maps and summary statistics for the diversity of tree species within the major ecoregions of Oregon.  It does not report species richness estimates or diversity metrics such as alpha, beta and gamma diversity.  Nonetheless, the most recent FIA 5-year report (Donnegan et al.  2008) includes a section on Lichen and Plant Biodiversity based on the suite of forest health indicators (Gray and Azuma 2005; Jovan 2008).  Other biological diversity research conducted by the US Forest Service Pacific Northwest Research Station can be accessed via: http://www.fs.fed.us/pnw/ 
 
This indicator does not include reporting and mapping the dead wood components in forest ecosystems.  Fallen trees, dead snags, and other dead wood provide habitat features for a variety of wildlife and invertebrate species.  The FIA five-year report (Donnegan et al.  2008) for Oregon included a section on dead wood (http://www.fs.fed.us/pnw/publications/gtr765/, pages 42-48).  FIA analyzed data on snags and down wood collected by FIA crews on more than 2,600 field plots in the state. In the five-year report, the analyses for dead wood is described in broad terms at the statewide level, with comparisons between western Oregon and eastern Oregon.
 
Additional information for this indicator is available on the  Indicator E.a. Data Availability and Analysis web page.  This information describes the data that is available for the metrics, a description of methodologies, discusses the results, and, finally, contemplates new information technologies and possibilities.
 

Modeling and Mapping Regions
 

An analysis project was undertaken at Oregon State University that integrated existing inventory data to generate detailed maps of existing forest vegetation and land cover across all ownerships in the Pacific Coast States.
 
The mapping analysis was separated into eight ecoregions across Oregon and the imputation of forested attributes from sampled locations to the greater forested ecosystems consisted of a mathematical technique known as Gradient Nearest Neighbor, or GNN - a technique used to map detailed vegetation composition and structure for areas of forest and woodland.  More specific information on the data availability and analysis is available on the Indicator E.a. Data Availability and Analysis web page.
 
GNN models and maps have been developed for 10 modeling regions for Oregon and part of California and Washington.  These modeling regions approximate Level III ecoregions of the conterminous United States.   The modeling regions depicted in Figure 1 include 1) Columbia Plateau - Washington, 2) Blue Mountains, 3) Northern Basin and Range 4) East Cascades, North, 5) East Cascades, South, 6) Western Cascades 7) Klamath Mountains., 8) Willamette Valley, 9) Coast Range, 10) Eastern Cascades - California.  The Columbia Plateau - Washington and Eastern Cascades - California are excluded from this analysis.
Ecosystem Region Map   
Figure 1. GNN Modeling Regions
 
The following reports illustrate how the GNN data can be reported and displayed for this indicator.  The graphics correspond to the amount of area in each forest type as represented by the dominant tree species, the size class of trees using quadratic mean diameter (QMD), and the amount of forest cover.  Each of these sets of information are organized according to the six IMAP mapping regions.  The GNN methodology assigned a forest type based on the single tree species (using 2000 PLANTS database symbols) that accounts for the most basal area at a sampling site. If there were multiple species with the same amount of basal area then trees-per-hectare was used as a tie breaker.
 

Report: West Cascades Mapping Region (Mapping Region 6)
This is a graphic of a vicinity map for Oregon that displays the location of the West Cascades Mapping Region.
 
This mountainous region extends from the Columbia River Gorge south almost to the California border.  Total area is approximately 2.9 million hectares (ha) (7.1 million acres), 95% (2.7 million ha, 6.8 million acres) of which is considered forest.
 
Figure 2 shows the variety of forest types, based on dominant tree species, distributed across the West Cascades mapping region.
 
The GNN data provides another forest type designation with a finer level of distinction for the diversity of forest types than the dominant species categorization.  A mapped display using the finer forest type designation is more complex than Figure 2 and more difficult to show distinctions between the major differences.  The number of forest subtypes within each dominant species category are listed in Table 2
 
Figure 3 displays how the GNN modeling distributed the average size of trees across the West Cascades mapping region.  There are six subcategories for this GNN output variable ranging from the smallest size class designation, “shrub/seedling,” to the largest, “giant tree.”  The size class designations are described in Johnson and Oneil’s (2001) compilation of wildlife-habitat relations in Oregon and Washington.
 
Figure 4 shows the amount of area of each size class arranged by forest type based on dominant tree species.  Most notable in this summary is the approximate 446,000 ha (~1,102,090 acres) of Douglas-fir-dominated forestland in the large tree category.  A notable comparison is that the estimated amount of area in each of the size class designations for the Douglas-fir-type was more than twice the amount of area in any of the size designations for mountain hemlock-dominated forestland.
 
Figure 5 shows the distribution of the percent canopy cover estimates across this mapping region. Estimates for canopy cover were generated with the Forest Vegetation Simulator.  A little more than 65 % of the forested area in this mapping region has a canopy cover estimate greater than 70%.  A comparison of the distribution of size classes in Figure 3 and the percent cover estimates of Figure 5 shows that forested areas with large trees were weakly correlated (R2 = 0.18) with forests with high canopy cover estimates.  Forest types with highest average percent canopy cover were mountain hemlock (84 %), Pacific silver fir (82%), western hemlock (78%), western redcedar (74), Shasta red fir (74%), subalpine fir (73%), black cottonwood (73%), and Douglas-fir (70%), while forests dominated by willow (< 1%), Oregon white oak (8%), western white pine (16%), and California black oak (17%) were among those with the lowest average percent canopy cover. 
 
The data for this mapping region's forest species, the average percent of canopy cover, area (hectares and acres), the percent of total forested area, and numbers of forest subtypes is included in the Table 2 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the West Cascades Mapping Region 
 

Report: Blue Mountains Mapping Region (Mapping Region 2)
This is a graphic of a vicinity map of Oregon depicting the location of the Blue Mountains Mapping Region.
 
The total area encompassed by this mapping region is 8,946,761 ha (22,107,927 acres), 5,191,871 ha (12,829,392 acres) of it considered forestland.  It contains the Ochoco, Blue, and Wallowa mountain ranges and five wilderness areas.  It is characterized as having deep canyons, glacially cut gorges, dissected plateaus, broad alluvial river valleys, numerous mountain lakes, meadows, and, of course, forests.   The area experiences short dry summers and long cold winters.  Precipitation ranges between 15 and 20 inches per year, with some of the mountain ranges receiving as much as 35 inches.  The Blue Mountains have been subdivided into fourteen smaller ecoregions reflecting the diversity of plant life and geology.
 
Figure 6 displays the variety of forest types based on dominant species distributed across this mapping region. Forests dominated by ponderosa pine comprise nearly 34% of the forested area followed by juniper with approximately 19% and Douglas-fir with 16%.  Forests dominated by Douglas-fir have the highest number of different subtypes (12) followed by lodgepole pine (10).  This region was historically dominated by forests with open stands of very old ponderosa pine with large diameters.  A combination of land use practices has altered these historical patterns to the conditions reported here (Langston 1995).  Ponderosa pine is distributed throughout the forested areas of this region except for the higher elevations.  Juniper-dominated forests are distributed primarily in the western and southern portions of this region.  Douglas-fir and grand fir are distributed less widely than ponderosa pine and lodgepole even less so.  Engelmann spruce occurs in specific areas of higher elevation.   
 
Figure 7 displays the distribution of the average size of trees and Figure 8 shows the amount of area of each size class arranged by dominant species forest type across this mapping region.  Forested areas are dominated by the small tree diameter class in the ponderosa pine, Douglas-fir, and grand fir forest types.  A pattern of decreasing area in the medium and large tree size classes is relatively consistent for each of these three forest types.  Most of the forested area classified as juniper and lodgepole pine are in the sapling/pole and small tree diameter classes.  The large tree and giant tree categories would have had significantly more area represented in Figure 7 and Figure 8 at the turn of the century than the current representation, especially for the ponderosa pine forest types.
 
Figure 9 displays the distribution of the percent canopy cover estimates across this mapping region.  The juniper forest type had the lowest average percent canopy cover while the forest types that occur at higher elevations in the region - such as Engelmann spruce, mountain hemlock, and subalpine fir - had the highest average percent canopy cover.  Fire is a chronic disturbance agent in this region and was a major factor in creating the open stands of large ponderosa pine reported in the early 1900’s (Langston 1995).  Timber harvest, livestock grazing, and the suppression of wildfires are the factors that have contributed to creating the current forest conditions.  The area of land classified as juniper forest has increased throughout the Blue Mountains mapping region and southeast Oregon from approximately 420,000 acres in 1936 to 3.3 million acres in 1999 (Azuma et al. 2005).  Expansion of juniper has a pronounced effect on the landscape by outcompeting ungulate-palatable vegetation, reducing soil absorption of precipitation, and changing the composition of wildlife.
 
The data for this mapping region's forest species, the average percent of canopy cover, area (hectares and acres), the percent of total forested area, and numbers of forest subtypes is included in the Table 3 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the Blue Mountains Mapping Region 
 

Report: Coast Range Mapping Region (Mapping Region 9)
This is a graphic of a vicinity map of Oregon depicting the location of the Coast Range Mapping Region.
 
The total area of this mapping region is 2,361,254 ha (5,834,786), with 2,083,555 ha (5,148,577 ac) of it identified as forestland.  Although elevations in the Coast Range rarely exceed 760 meters (2,500 ft), the region’s topography is mountainous with numerous rivers and streams.  Annual precipitation averages 152 to 200 cm (60 to 80 in) along the coast with some inland areas receiving over 250 cm (100 in). 
 
Over 68 % of the forested area is dominated by Douglas-fir which is ubiquitous throughout the region and has 23 different forest classification subtypes (Figure 10 and Table 4).  Approximately 12% of the forestland is dominated by Douglas-fir’s deciduous associate, red alder, which is distributed from the northern to the southern boundary of the region.  Western hemlock- and sitka spruce-dominated forests are distributed primarily in the northern half of the region, comprise 7.8% and 2.5% of the forested area, and contain seven and five different forest classification subtypes, respectively.  Lodgepole pine, referred to as shorepine or beachpine, comprises approximately 1% of the forested area, has a distribution limited to coastal areas, and has five different classification subtypes.  Research based on historical (1939) and recent (1993) aerial photos of a west central portion of the Coast Range showed that shrub fields and hardwoods have declined by 16%.  Changes in the spatial distribution of shrub and hardwood types resulted in more area in this type at lower slope positions and closer to streams and roads than historical. 
 
Figure 11 displays the distribution of the average size of trees across the Coast Range mapping region. Changes in forest structure in the Coast Range from historical conditions have been greater than changes in species distributions.  Focused research on the maritime-influenced region of Oregon, generally below 2000 ft in elevation, has shown that old growth forests declined from 14.2 million acres to 4.9 million acres in the period 1945 to1992 (Bolsinger and Waddell 1993).  The amount of area GNN classified as the giant tree size class for the Coast Range is 171,625 ha (424,095 acres) or about 8% of the forested area.  Approximately 77% of the area classified as giant tree structure is owned by federal, state, or tribal governments, with the remainder in private ownership.  Nearly three-quarters of the area (73%) in the Coast Range was classified as belonging to the sapling/pole, small, and medium tree size classes (Figure 12).
 
Figure 13 displays the distribution of the percent canopy cover estimates across this mapping region. Most of the area (73%) in this region’s forested area has a percent canopy cover estimate of at least 40%, while approximately one-quarter of the forested area has a canopy cover estimate between 0 and 40% (Figure 13).  With over 65% of the forested area in some form of private ownership, this region has experienced a relatively high level of forest management that increased following implementation of the Northwest Forest Plan.  However, Forest Practice rules require replanting following harvest which leads to a short time interval for forested stands to remain in the low canopy cover classes.
 
The data for this mapping region's forest species, average percent of canopy cover, area (hectares and acres), percent of total forested area, and forest subtypes is included in the Table 4 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the Coast Range Mapping Region 

 

Report: Klamath Mountains Mapping Region (Mapping Region 7)
This is a graphic of a map of Oregon depicting the location of the Klamath Mountains Mapping Region.
The Klamath Mountains mapping region encompasses 1,633,982 ha (4,037,658 acres), with approximately 87% (1,418,126 ha; 3,504,265 acres) identified as some type of forestland.  Elevations in this mapping region range from 30 meters (100 ft) to over 2280 meters (7500 ft).  The area contains the Siskiyou Mountains, Marble Mountains, and Trinity Alps, along with the Wild Rogue and Kalmiopsis Wilderness areas.  This mapping region is one of the few parts of Oregon not shaped largely by volcanics and is geologically diverse, having large areas of metamorphic, sedimentary, granitic, and extrusive material.  The western part of the mapping region can receive up to three meters (120 in.) of precipitation while the interior can experience less than half of a meter (20 in).  The combination of diverse geology and climate provides the conditions for a high level of forest ecosystem diversity.  This mapping region was unglaciated during the Pleistocene Epoch and served as a refuge for northern plant species.  Historically, forests of this region experienced frequent fire and had considerably more area in old growth status than current conditions.  More recently, fires of the Silver Complex burned approximately 96,540 acres in 1987 and the Biscuit Fire burned approximately 500,000 acres in 2002.
 
Figure 14 displays the variety of forest types, based on dominant species, distributed across the Klamath Mountains mapping region. Within the GNN database there are 29 different forest types defined by dominant species and 158 forest subtypes (Table 5).  Douglas-fir is ubiquitous in this region, dominating 57.6% of the forested area with 22 different subtypes.  A significant amount of area is dominated by 12 different hardwood species with 58 subtypes that are distributed more specific than Douglas-fir.  This mapping region has been subdivided into seven smaller ecoregions reflecting the geographical segregation of forest types and geologic conditions.  Areas with Port Orford cedar have declined from historic amounts because of an introduced root pathogen (Phytophthera lateralis).
 
Figure 15 displays the distribution of the average size of trees across the mapping region and Figure 16 shows the amount of area of each size class arranged by dominant species forest type for this mapping region.  More than 66% of the forests in this region were classified as the sapling pole or small tree size classes.  About 24% of the area dominated by Douglas-fir (199,000 ha; 492,498 acres) is designated as large tree or giant tree forest size classes.  The giant tree size class also has sizeable representation in forests dominated by white fir, shasta red fir, mountain hemlock, and tanoak.  The geographical distribution of size classes shows that the large tree and giant tree classes have definite areas of concentration whereas the other classes are more or less distributed throughout the region.
 
Figure 17 displays the distribution of the percent canopy cover estimates across this mapping region.  Nearly half of the forested area was estimated to have at least 70% canopy cover.  All but nine of the forest types had average percent canopy cover estimates of at least 50% and nine had estimates of at least 70%.  Jeffrey pine dominated forests had the lowest average percent canopy cover estimate (26%).  The area dominated by western white pine adjacent to the southern boundary and west of center emerges as a distinct area and forest type with low canopy cover.
 
The data for this mapping region's forest species, average percent of canopy cover, area (hectares and acres), the percent of total forested area, and forest subtypes is included in the Table 5 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the Klamath Mountains Mapping Region
 

Report: East Cascades South Mapping Region (Mapping Region 5)
This is a graphic of a map of Oregon depicting the location of the East Cascades South Mapping Region.
 
The total area of this mapping region is 2,483,476 ha (6,136,803 acres), of which 1,813,587 ha (4,481,471 acres) is classified as forest.  This mapping region includes the Klamath Basin and mountainous areas that extend from Paulina Peak near Bend southward to the Warner Mountains east of Lakeview.  Much of this mapping region is covered in a layer of pumice from Mount Mazama eruptions that range in depth from a few centimeters up to 16 meters (50 ft).  Elevation ranges from 841 meters (2762 ft) up to 2564 meters (8412 ft).
 
Figure 18 displays the variety of forest types, based on dominant species, distributed across this mapping region.  Five tree species dominate the forests of this mapping region, with ponderosa pine comprising half the area with ten subtypes.  Lodgepole pine dominates 23% and white fir approximately 13% of the forested area, and each also has ten forest subtypes.  Juniper, with two subtypes, dominates eight percent of the forested area and Douglas-fir dominates just a little over one percent with nine subtypes. 
 
Figure 19 displays the distribution of the average size of trees across the East Cascades South Mapping Region.  More than three-fourths of the forested area consists of stands in the sapling/pole and small tree size classes.
 
Figure 20 shows the amount of area of each size class arranged by dominant species forest type for this mapping region. The ponderosa pine- and white fir-dominated forests contain the bulk of area in the large tree size class, which occupies about five percent of the forested area.  In the giant tree size class there is approximately 3000 ha (7300 acres) of ponderosa pine-dominated forest, 1148 ha (2837 acres) of white fir, 148 ha (367 acres) of Douglas-fir, and 309 ha (763 acres) of Shasta red fir.  The majority of area with forests classified in the giant tree size class is located west of Klamath Falls near Brown Mountain and Lake of the Woods.
 
Figure 21 displays the distribution of the percent canopy cover estimates across this mapping region.  More than 90% of the forested area has an average percent canopy cover less than 70% and more than half of the forests have an average percent canopy cover less than 40%.  Many of the areas with percent canopy cover values greater than 70% (Figure 21) are associated with forests dominated by lodgepole pine and white fir, and are distributed in relatively distinct patches in several locations throughout the region. Pacific silver fir and western hemlock-dominated forests, although comprising less than one percent of the region, had the highest average percent canopy cover estimates (Table 6).
 
Even though approximately half of the forested area is dominated by ponderosa pine, decades of timber management, livestock grazing, and fire suppression have altered the structure of these forests from historic conditions.  The result is a shift to mixed conifer forests made up of denser stands of smaller sized trees.  The large amount of area dominated by lodgepole pine forests makes this area susceptible to infestations of mountain pine beetle which have recently affected approximately 300,000 acres of public and private forestland.  The mountain pine beetle infestation has been spreading south since the early 1990s from the southern portion of the Silver Lake Ranger District. The infestation now is affecting lodgepole stands of portions of the Paisley and Bly Ranger Districts within this mapping region.
 
The data for this mapping region's forest species, the average percent of canopy cover, area (hectares and acres), the percent of total forested area, and forest subtypes is included in the Table 6 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the East Cascades South Mapping Region
 

Report: East Cascades North Mapping Region (Mapping Region 4)
This is a graphic of a vicinity map of Oregon depicting the location of the East Cascades North Mapping Region.
 
The total area for this mapping region is 556,048 ha (1,374,025 acres), with 73% or 406,034 ha (1,003,333 acres) of it classified as forest.  Its length from north to south is about 200 km (125 miles) and only about 51 km (30 miles) east to west.
 
This mapping region is similar in geology to the East Cascades South Mapping Region in terms of geology and climate.  The northern portion is characterized by steeply sloping, dissected mountains with high- to medium-gradient streams and glacial rock-basin lakes. Elevation varies from 66 m (216 ft) near the Columbia River up to 6,391 m (6,500 feet).  This region is in the rain shadow of the Cascade Mountain Range and therefore receives considerably less precipitation than the western side of the Cascade Mountains.  Nonetheless, annual precipitation varies across the region from above 40 inches in higher elevations to less than 10 inches in the eastern-most and low elevation areas.  The composition of plant species in this region is characteristic of areas susceptible to frequent wildfire and a dry, continental climate.  Approximately 99% of this mapping region is owned by private entities (53%), the United States Forest Service (42%), and the Bureau of Indian Affairs (4%).
 
Ponderosa pine, with eleven forest subtypes, dominates half of the forested area, similar to the mapping region to the south, but there is considerably more area (25%) dominated by Douglas-fir which is distributed in the northern and west part of the region and has 13 forest subtypes (Figure 22 and Table 7).  Oregon white oak, with only two subtypes, dominates approximately seven percent of the forested area.  Juniper, distributed in the lower elevations, and white fir, distributed in the higher elevations, each dominate five percent.  Juniper-dominated forests are comprised of only one subtype and white fir is comprised of five.  Lodgepole pine forests are comprised of eight subtypes.
 
Figure 23 displays the distribution of the average size of trees across the East Cascades North Mapping Region.  The large tree size class defines approximately 6% of the forest structure and the giant tree less than one percent.  Douglas-fir and ponderosa pine comprise most of the forest type belonging to the large tree size class. More than 50% of the forest area is classified as medium or small tree size class.  The sapling/pole size class is also considerable, with approximately 41% of the forested area.  Figure 24 shows the amount of area of each size class arranged by dominant species forest type for this mapping region.
 
Figure 25 displays the distribution of the percent canopy cover estimates across theis mapping region.  There is a distinct east-west gradient of percent canopy cover with the eastern portion, dominated by juniper, having canopy cover estimates below 10% and the western portions with estimates of 40% and above.  A little over 56% of the forested area has a canopy cover estimate of 40% and higher, 13.4% of that area with an estimate greater than 70%.
 
The data for this mapping region's forest species, the average percent of canopy cover, area (hectares and acres), the percent of total forested area, and forest subtypes is included in the Table 7 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the East Cascades North Mapping Region 
 

Report: South East Oregon Mapping Region (Mapping Region 3)
This is a graphic of a vicinity map of Oregon depicting the location of the South East Oregon Mapping Region.
 
Total area for this mapping region is 5,927,157 ha (14,646,324 acres), with approximately 186,818 ha (461,638 acres), or 3.2% of it considered forested.  Elevations range from 1250 meters (4100 ft) in the lowest basin to more than 2956 meters (9700 ft) on Steens Mountain. Two large wildlife refuges are located in this mapping region - Hart Mountain (112,757 ha; 278,630 acres) and Malheur (75,676 ha; 187,000 acres) National Wildlife Refuges - that comprise a little over three percent of the region’s land area. The topography of the region is considered basin and range, with numerous flat basins separated by isolated, generally north-south trending mountain ranges.  Soils are generally rocky and thin, low in organic matter, and high in minerals. Climate is arid, with most places receiving less than 30 cm (~12 in) of annual precipitation. Extreme changes in daily and seasonal temperature are common. 
 
The small amount of forested area of this mapping region is clearly dominated by juniper which amounts to over 92% of the forested areas (Figure 26).  Mountain mahogany and ponderosa pine each comprise a little over three percent of the forested area.  Each of the three forest types are distinct in that there are no forest subtypes identified within the GNN database.  Juniper is widespread and has been increasing throughout the mapping region.  Ponderosa pine has the largest presence in the Steens Mountain area but there are many small islands of various sizes scattered throughout the mapping region - most of them near the northern boundary and somewhat associated with drainage features.  Mountain mahogany also occurs in small patches that speckle the landscape at higher elevations such as Hart Mountain and Steens Mountain.
 
Figure 27 displays the distribution of the average size of trees across the South East Oregon Mapping Region.  There were no forested areas classified to the giant tree size class but a little over six percent of the forested area was classified as large tree, all of which was juniper-dominated.  More than 86% of the area is classified as sapling/pole or small tree size class, with 61% of that area classified as the sapling/pole class.  All of the ponderosa pine-dominated forest area was classified to the large tree size class.  All of the mountain mahogany forested areas were classified as sapling/pole size class.  Figure 28 shows the amount of area of each size class arranged by dominant species forest types for this mapping region.
 
Figure 29 displays the distribution of the percent canopy cover estimates across this mapping region. The majority of forested areas in this mapping region have relatively low canopy tree cover.  For example, over 90% of the forested area received a percent canopy cover estimate of less than 40%, with 32% having canopy cover less than 10% percent.  A little over one percent of the forests had a canopy cover estimate of 40 to 70% and no areas received an estimate of greater than 70%.  Juniper typically grows in multiaged stands with crown cover of less than 50 percent.  The most significant trend in this ecoregion is the increase in the amount of area estimated as juniper forest in Harney and Malheur Counties by 182,918 ha (452,000 acres) from 1936 to 1999 (Azuma 2005).
 
The data for this mapping region's forest species, average percent of canopy cover, area (hectares and acres), percent of total forested area, and forest subtypes is included in the Table 8 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the South East Oregon Mapping Region 
 

Report: Willamette Valley Mapping Region (Mapping Region 8)
This is a vicinity map of Oregon depicting the location of the Willamette Valley Mapping Region.
 
The total amount of area for this mapping region is 1,374,963 ha (3,397,609 acres), with 507,691 ha (1,254,532 acres) or 37% of it classified as forestland.  Elevation ranges from near sea level up to 787 m (2583 ft).  This mapping region, which contains the Willamette Valley and the adjacent foothills, is bounded on the east by the Cascade Mountain Range and on the west by the Coast Range.  The valley is a long alluvial plain with scattered groups of basalt hills.  Average annual precipitation is 102 cm (40 inches).  Prior to European settlement, the valley consisted of a mixture of forest, open savanna, prairie, and riparian woodlands.  Today, the valley consists of a mosaic of farms, suburbs, and cities, interspersed with small patches of grasslands and coniferous and hardwood forests.  This mapping region contains approximately 70% of Oregon’s human population and largest urban centers.
 
Douglas-fir, with 17 forest subtypes, dominates a little more than 64% of the forested area.  The total area of the three most dominant hardwood species - bigleaf maple with four subtypes, Oregon white oak with three subtypes, and red alder with eight subtypes - amounts to 15% of the forested area.  The majority of the forest is distributed near the edges of the mapping region (Figure 30).  The northwestern portion of the mapping region contains the bulk of area dominated by western redcedar, alder, and bigleaf maple.  The historical amount of oak woodlands may have covered half of this mapping ecoregion prior to European settlement.  Much of the oak woodlands and savannas have been converted to agriculture or allowed to succeed to conifer forests through the suppression of fire.
 
Eleven percent of the forested area is classified as regenerating forest or the shrub/seedling size class with a relatively ubiquitous distribution (Figure 31).  The sapling pole size class comprises almost 30% of the forests, the small tree size class about 28%, the medium tree size class a little more than 18%, and the large tree size class close to 12%.  These four structure classes are distributed rather continuously throughout the forested areas, except for a concentration of the large tree class in the northwestern portion of the mapping region.  The giant tree size class is represented completely by the Douglas-fir-dominated forests (Figure 32), comprises about 2% of the forested area, and has a scattered distribution, with a concentration of area in the southern part of the mapping region. 
 
Nearly 41% of the forested area could be considered closed-canopy with a canopy cover estimate greater than 70% (Figure 33).  Areas with 40 to 70% canopy cover amount to almost 33% of the forest landscape.  Forests with canopy cover estimates ranging between 10 and 40% make up about 14% of the total forested area, and the open forests with canopy cover estimates less than 10% make up about 12%.  Each of the canopy cover classes has a geographic distribution that is relatively continuous throughout the mapping region.
 
The data for this mapping region's forest species, the average percent of canopy cover, area (hectares and acres), the percent of total forested area, and forest subtypes is included in the Table 9 summary statistics.
 
 
Indicator E.a. - Maps and Data for the Report on the Willamette Valley Mapping Region 
 
 

Research and Related Information
  • Van Mantgem, P.J., Stephenson, N.L., Byrne, J.C., Daniels, L.D., Franklin, J.F., Fule, P.Z., Harmon, M.E., Larson, A.J., Smith, J.M., Taylor, A.H., Veblen, T.T.  2009.  "Widespread increase of tree mortality rates in the Western United States."  Science. Vol 323: 521-524.
  • Oregon Department of Forestry, USDA Forest Service.  2009.  Forest health highlights.  Technical Report available at:  http://www.fs.fed.us/r6/nr/fid/health/2008highlights-or.pdf
  • Ohmann, JL, MJ Gregory. 2002. Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, USA. Canadian Journal of Forest Research 32(4):725-741.
  • Ohmann, JL, TA Spies. 1998. Regional gradient analysis and spatial pattern of woody plant communities of Oregon forests. Ecological Monographs 68(2):151-182.
  • Gray, A. N., and D. L. Azuma. 2005. Repeatability andimplementation of a forest vegetation indicator. Ecological Indicators 5:57–71.
  • Donnegan, J.; Campbell, S.; Azuma, D., tech. eds. 2008. Oregon’s forest resources, 2001-2005: five-year Forest Inventory and Analysis report. Gen. Tech. Rep. PNW-GTR-765. Portland, OR: U.S. Forest Service, Pacific Northwest Research Station. 186 p.
  • Jovan, S. 2008. Lichen bioindication of biodiversity, air quality, and climate: baseline results from monitoring in Washington, Oregon, and California. Gen.Tech. Rep. PNW-GTR-737. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 115 p.
 

Evaluations by the Oregon Roundtable on Sustainable Forests on this indicator
 
 
 

Metrics and Data Sources


Metric
Data Source
Diversity of Forest Types
Average tree size class
Percent forest cover
U.S. Forest Service Forest Inventory and Assessment
Gradient Nearest Neighbor Vegetation Mapping.  Landscape Ecology, Mapping and Analysis Lab, Oregon State Unviersity
Vegetation change detectionU.S. Forest Service Forest Inventory and Assessment
Oregon Climate Change Research Institute
 
Metrics for vegetation change detection are currently being developed in collaboration with researchers at the Oregon Climate Change Research Institute.  These metrics may include changes in the geographical extent of individual tree, shrub, and herbaceous species, along with differences in the spatial distribution of seedlings relative to mature trees within and among inventory occasions.
 
Indicator E.a. Data Availability and Analysis web page

Related State, National, or International Indicators
  • Montreal Process: Criterion 1 – Conservation of biological diversity: 2003 Indicator 1: Extent of area by forest type relative to total forest area; 2003 Indicator 2: Extent of area by forest type and by age class or successional stage; 2003 Indicator 3: Extent of area by forest type in protected area categories as defined by IUCN or other classification systems; 2003Indicator 4: Extent of areas by forest type in protected areas defined by age class or successional stage; 2003 Indicator 5 (2010 Indicator 3): Fragmentation of forest types; and 2010 Indicator 1: Area and percent of forest by forest ecosystem type, successional stage, age class, and forest ownership or tenure
  • Heinz Center:  Forest types; At risk native species; Area covered by non-native plants; Forest types with significantly reduced area
  • British Columbia: Indicator 1—Ecosystem Diversity  
  • Northeastern Area:  1.4—Status of forest/woodland communities and species of concern
  • Mt. Hood National Forest: Long-term community dynamics; landscape diversity; species richness; special habitats
  • Oregon Benchmarks: Environment--88:  Percent of monitored terrestrial species not at risk
  • Oregon Benchmarks: Environment--89:  Percent of land in Oregon that is a natural habitat
  • Oregon State of the Environment Report: Amount of commercial forest types in different structural stages compared to amounts in healthy forest systems; Change in area of native vegetation types