1. Forests less than 150 years old |
go to Key A |
1. Forests over 150 years old |
2 |
2. Forests above 1100 m (3,600 ft) elevation |
go to Key B |
2. Forests below 1100 m (3,600 ft) elevation |
3 |
3. Forests of valleys or toeslopes or wet sideslopes and benches
Oplopanax horridum and/or ferns (Polystichum munitum, Blechnum
spicant, Gymnocarpium dryopteris, Athyrium filix-femina)
common |
go to Key C |
3. Forests of dry or mesic (but not wet) sideslopes, ridges, or
benches. Oplopanax horridum absent or rare |
4 |
4. Forests of mesic slopes and benches. Dominant trees are
Pseudotsuga menziesii, Tsuga heterophylla, Abies amabilis, Abies
procera, and sometimes Chamaecyparis nootkatensis |
go to Key D |
4. Forests of dry slopes and exposures. Dominant trees are
Pseudotsuga menziesii, Tsuga heterophylla, Thuja plicata, and
sometimes Pinus monticola |
go to Key E |
Key A. Forests Less Than 150 Years Old |
1. Abies lasiocarpa dominates regeneration and canopy |
Abies lasiocarpa/Valeriana sitchensis |
1. Abies lasiocarpa minor or absent |
2 |
2. Alnus rubra dominates or codominates canopy |
Alnus rubra/Rubus spectabilis |
2. Alnus rubra minor or absent |
3 |
3. Menziesia ferruginea cover greater than 5 percent.
Abies amabilis dominates or codominates canopy |
Abies amabilis/Menziesia ferruginea |
3. Menziesia ferruginea cover less than 5 percent,
Pseudotsuga menziesii usually dominant or codominant in
canopy |
4 |
4. Ceanothus velutinus present |
Pseudotsuga menziesii/Ceanothus velutinus |
4. Ceanothus velutinus absent |
5 |
5. Xerophyllum tenax cover less than 5 percent, and
Viola sempervirens cover more than 1 percent |
Pseudotsuga menziesii/Viola sempervirens |
5. Xerophyllum tenax cover more than 5 percent and/or
Viola sempervirens cover less than 1 percent |
Pseudotsuga menziesii/Xerophyllum tenax |
Key B. High-Elevation Forests, Tsuga mertensiana Zone |
1. Oplopanax horridum more than 2 percent cover |
Abies amabilis/Oplopanax horridum |
1. Oplopanax horridum less than 2 percent cover |
2 |
2. Gaultheria shallon more than 5 percent cover |
Abies amabilis/Gaultheria shallon |
2. Gaultheria shallon less than 5 percent cover |
3 |
3. Berberis nervosa more than 3 percent cover |
Abies amabilis/Berberis nervosa |
3. Berberis nervosa less than 3 percent cover |
4 |
4. Abies lasiocarpa dominates regeneration and canopy,
Valeriana sitchensis more than 5 percent cover |
Abies lasiocarpa/Valeriana sitchensis |
4. Abies lasiocarpa minor or absent, Valeriana
sitchensis usually less than 5 percent cover |
5 |
5. Xerophyllum tenax more than 10 percent cover |
Abies amabilis/Xerophyllum tenax |
5. Xerophyllum tenax less than 10 percent cover |
6 |
6. Chamaecyparis nootkatensis at least codominant in
canopy or regeneration and either Vaccinium ovalifolium or
Rubus pedatus cover more than 10 percent |
Chamaecyparis nootkatensis/Vaccinium ovalifolium |
6. Chamaecyparis nootkatensis absent or minor or both
Vaccinium ovalifolium and Rubus pedatus less than 10
percent cover |
7 |
7. Shrub cover appreciably less than the usually profuse herb
cover |
Abies amabilis/Tiarella unifoliata |
7. Shrub cover equal to or greater than herb cover |
8 |
8. Menziesia ferruginea cover greater than 5 percent or
Rhododendron albiflorum cover greater than 5 percent or
Vaccinium alaskaense cover greater than 5 percent |
9 |
8. Menziesia ferruginea or Rhododendron albiflorum
or Vaccinium alaskaense cover less than 5 percent |
11 |
9. Vaccinium alaskaense cover greater than 10 percent or
Rhododendron albiflorum and Menziesia ferruginea cover
both less than 1 percent |
Abies amabilis/Vaccinium alaskaense, go to
key D. step 3 |
9. Vaccinium alaskaense cover less than 10 percent and
Rhododendron albiflorum or Menziesia ferruginea cover
greater than 1 percent |
10 |
10. Rhododendron albiflorum cover greater than
Menziesia ferruginea cover |
Abies amabilis/Rhododendron albiflorum |
10. Rhododendron albiflorum cover less than Menziesia
ferruginea cover |
Abies amabilis/Menziesia ferruginea |
11. Erythronium montanum cover greater than 10 percent |
Abies amabilis/Rubus lasiococcus, Erythronium montanum phase |
11. Erythronium montanum cover less than 10
percent |
Abies amabilis/Rubus lasiococcus, Rubus lasiococcus
phase |
Key C. Forests of Wet Sites Below 1100 m (3,600 ft) Elevation |
1. Oplopanax horridum cover greater than 2 percent |
2 |
1. Oplopanax horridum cover less than 2 percent |
3 |
2. Abies amabilis codominant or dominant in canopy or regeneration |
Abies amabilis/Oplopanax horridum |
2. Abies amabilis minor |
Tsuga heterophylla/Oplopanax horridum |
3. Abies amabilis codominant in regeneration or canopy |
Tsuga heterophylla/Polystichum munitum, Abies amabilis phase |
3. Abies amabilis minor |
Tsuga heterophylla/Polystichum munitum |
Key D. Forests of Mesic Sites Below 1100 m (3,600 ft) Elevation |
1. Abies amabilis minor in canopy and regeneration,
Achlys triphylla cover usually greater than 10 percent |
Tsuga heterophylla/Achlys triphylla |
1. Abies amabilis dominant or codominant |
2 |
2. Total cover of shrubs greater than or equal to total cover of
herbs |
Abies amabilis/Vaccinium alaskaense phases |
3 |
2. Shrub cover less than the rather profuse herb cover |
Abies amabilis/Tiarella unifoliata |
3. Chamaecyparis nootkatensis codominant in canopy and
regeneration |
Chamaecyparis nootkatensis phase |
3. Chamaecyparis nootkatensis minor |
4 |
4. Rubus pedatus cover greater than 10 percent |
Rubus pedatus phase |
4. Rubus pedatus cover less than 10 percent |
5 |
5. Berberis nervosa cover greater than 5
percent |
Berberis nervosa phase |
5. Berberis nervosa cover less than 5 percent |
Typical Vaccinium alaskaense phase |
Key E. Forests of Dry Sites Below 1100 m (3,600 ft) Elevation |
1. Gaultheria shallon cover greater than 5 percent |
2 |
1. Gaultheria shallon cover less than 5 percent,
Berberis nervosa cover usually greater than 5 percent |
Abies amabilis/Berberis nervosa |
2. Abies amabilis dominant or codominant in canopy or
regeneration, Chamaecyparis nootkatensis often present |
Abies amabilis/Gaultheria shallon |
2. Abies amabilis minor, Chamaecyparis
nootkatensis never present |
Tsuga heterophylla/Gaultheria shallon |