Plant Community Classification Intro and Key

Plant communities have been described in the Chugach National Forest and on the Kenai Lowlands. A few communities are named for the Matanuska Susitna Valley.

Key to the Wetland Plant Communities of the Kenai Lowlands

Wetland communities: Peat greater than 20 cm thick, or water table at or near the surface for a significant portion of the growing season, or communities regularly flooded by fresh or salt water. Some communities keyed here are not always wetlands regulated under the Clean Water Act.

1. Trees (>1.5 meters tall) cover more than 10%..................................................	Forested Communities, 2
1. Trees less than 10% cover...................................................................................	16

FORESTED COMMUNITIES
2. Lutz spruce (Picea X Lutzii) the dominant tree...............................................	Lutz Spruce Forests, 3
2. Another tree dominant........................................................................................	12
3. Rusty menziesia (Menziesia ferruginea ) cover > 7%.....................................	Lutz spruce / Rusty menziesia / Field horsetail
3. Rusty menziesia not present, or only a few plants............................................	4
4. Sitka alder (Alnus viridis ssp. sinuata ) cover > 7%.......................................	Lutz spruce / Sitka alder / Field horsetail
4. Sitka alder not present, or only a few plants....................................................	5
5. Barclay's willow (Salix barclayii) cover > 7%...................................................	6
5. Barclay's willow absent or only a few plants.......................................................	9
6. Field horsetail (Equisetum arvense) cover > 10%, often > 30%..............	7
6. Field horsetail < 10% cover, crowberry (Empetrum nigrum ) cover > 20%............................................................................................................................	8
7. Bluejoint (Calamagrostis canadensis ) cover > 20%, plants present uniformly in stand.....................................................................................................	Lutz spruce / Barclay's willow / Bluejoint
7. Bluejoint cover may exceed 20%, but not uniform, field horsetail cover > 20% and uniform.......................................................................................................	Lutz spruce / Barclay's willow / Field horsetail
8. Crowberry cover > 25%, field horsetail cover > 15%..................................	Lutz spruce / Barclay's willow / Field horsetail / Crowberry
8. Crowberry cover usually exceeds 25%, but field horsetail cover is low, and other ericaceous shrubs co-dominate..............................................................	Lutz spruce / Barclay's willow / Ericaceous shrub
9. Oakfern (Gymnocarpium dryopteris ) cover exceeds 10%.............................	10
9. Oakfern absent, or only a few plants...................................................................	11
10. Bluejoint cover > 10%.....................................................................................	Lutz spruce / Oakfern - Bluejoint
10. Bluejoint only a few clumps; Field horsetail cover > 15%........................	Lutz spruce / Field horsetail - Oakfern
11. Lutz spruce as an open woodland, or stunted trees; dwarf birch and field horsetail cover > 10% .............................................................................................	Lutz spruce / Field horsetail - Oakfern
11. Lutz spruce canopy open or denser; bluejoint cover > 10%, often > 25%	Lutz spruce / Field horsetail - Bluejoint
12. Black spruce (Picea mariana) cover > 7%..................................................	13
12. Balsam poplar (Populus balsamifera) dominant.........................................	Balsam poplar / Thinleaf alder
13. Lingonberry (Vaccinium vitis-idaea ) cover > 10%......................................	Black spruce / Crowberry – Lingonberry
13. Lingonberry absent, or only scattered at bases of trees.................................	14
14. Dwarf birch (Betula nana ) cover > 20%; Labrador tea (Ledum palustre ssp. decumbens ) cover low, scattered....................................................................	Black spruce / Field horsetail - Dwarf birch
14. Labrador tea cover usually >20%; dwarf birch cover low, scattered.........	15
15. Horsetail (usually woodland h., E. sylvaticum) cover > 10%........................	Black spruce / Woodland horsetail - Labrador tea (see note at end of description)
15. Horsetails absent, or only a few stems.............................................................	Black spruce / Labrador tea

16. Shrub cover > 10%, usually > 20%................................................................	Shrub communities, 17
16. Graminoids or herbs dominant, shrubs inconspicuous components............	42

SHRUB COMMUNITIES
17. Thinleaf alder (Alnus incana ssp. tenuifolia ) dominates, often > 40%......	Thinleaf alder / Bluejoint
17. Thinleaf alder only present as scattered clumps, if at all...............................	18
18. Sitka alder (Alnus viridis ssp. sinuata) cover typically > 50%..................	19
18. Sitka alder , if present, at < 20% cover...........................................................	21
19. Shieldfern the dominant understory component.............................................	Sitka alder / Shieldfern
19. Shieldfern not the dominant understory..........................................................	20
20. Field horsetail the dominant understory plant..............................................	Sitka alder / Field horsetail
20. Marsh horsetail (Equisetum palustre ) the dominant understory plant.....	Sitka alder / Marsh horsetail
21. Willows (Salix spp.) the dominant shrub.........................................................	22
21. Willows not dominant........................................................................................	28
22. Feltleaf willow (Salix alexensis) dominates.................................................	Feltleaf willow / Bluejoint
22. Another willow dominates...............................................................................	23
23. Tealeaf willow (Salix pulchra ) dominates shrubs..........................................	Tealeaf willow / Crowberry
23. Barclay's willow (Salix barclayi ) dominates.....................................................	24
24. Bluejoint cover > 25%, codominant with Barclay's willow...........................	25
24. Bluejoint cover <10%, a diverse herbaceous, graminoid and shrub community present...................................................................................................	Barclay's willow / Rich
25. No other plants co-dominate with Barclay's willow and bluejoint..................	Barclay's willow / Bluejoint
25. Other plants codominate at > 10% cover.........................................................	26
26. Tufted hairgrass (Deschampsia caespitosa ) co-dominates, sometimes with higher cover than bluejoint .............................................................................	Barclay's willow / Tufted hairgrass – Bluejoint
26. Tufted hairgrass not present, or only a few clumps......................................	27
27. Marsh fivefinger a dominant layer under the willow and bluejoint................	Barclay's willow / Bluejoint / Marsh fivefinger
27. Marsh fivefinger not typically present, or only scattered in a few micro-topographic low places; field horsetail cover > 20%...............................	Barclay's willow / Bluejoint - Field horsetail
28. Crowberry cover > 20%, frequently > 50%..................................................	29
28. Crowberry cover < 10%, if present...............................................................	31
29. Fewflower sedge (Carex pauciflora ) clumps dominate in micro- topographic lows.......................................................................................................
29. fewflower sedge, if present, only as scattered clumps.............................
30. Labrador tea , with dwarf birch , overtops crowberry. .....................................
30. Bog blueberry , with dwarf birch , overtops crowberry...................................	Crowberry – Bog blueberry
31. Bog blueberry the dominant shrub...................................................................	Fewflower sedge - Crowberry
31. Bog blueberry only as scattered plants, if present..........................................	30
32. Dwarf birch and many-flowered sedge (Carex pluriflora ) the co- dominants...................................................................................................................	Crowberry - Labrador tea
32. Dwarf birch cover usually > 20%; hairgrass (usually D. caespitosa, but sometimes D. beringiana) stems prominent, though frequently at low cover...	Bog blueberry - Dwarf birch – Tufted hairgrass
33. Sweetgale (Myrica gale ) the dominant shrub..................................................	34
33. Sweetgale not present, or as scattered plants...................................................	38
34. Livid sedge (Carex livida ) intermingled, or in separate close-by stands with sweetgale...........................................................................................................	Sweetgale - Livid sedge
34. Livid sedge not present, or only a few stems................................................	35
35. Shrubby cinquefoil (Dasiphora floribunda ) present, common....................	Sweetgale - Shrubby cinquefoil
35. Shrubby cinquefoil absent, or rare....................................................................	36
36. Bluejoint common, sweetgale about 60cm or more tall.............................	Sweetgale - Bluejoint
36. Bluejoint not common, typically absent........................................................	37
37. Dwarf birch and water horsetail (Equisetum fluviatile ) present with sweetgale in a low thicket, sometimes with hummocks and scattered bog blueberry ....................................................................................................................	Sweetgale - Dwarf birch / Water horsetail
37. No thicket; sweetgale cover low, with tufted bulrush clumps either separate, as a mosaic with sweetgale, or intermingled..........................................	Tufted bulrush - Sweetgale
38. Dwarf birch the sole dominant shrub (cover > about 10%)..........................	39
38. Overall shrub cover low; Sphagnum spp. clearly visible through the shrub layer. If dwarf birch is present, shrubs co-dominate..................................	41
39. Bluejoint overtops dwarf birch in a tussocky – hummocky, wet stand.........	Bluejoint / Dwarf birch
39. Bluejoint not present.........................................................................................	40
40. Tufted bulrush intermingled with dwarf birch ; or a mosaic with tufted bulrush occupying micro-topographic lows and dwarf birch on highs................	Tufted bulrush – Dwarf birch
40. Fewflower sedge intermingled with dwarf birch, or a mosaic as above. Tufted bulrush absent or rare...................................................................................	Fewflower sedge - Dwarf birch
41. Leatherleaf (Chamaedaphne calyculata ) the dominant shrub......................	Sphagnum moss – Leatherleaf
41. Leatherleaf absent or present as scattered individuals....................................	Sphagnum moss – Ericaceous shrub
42. A grass or sedge dominates vascular cover......................................................	Graminoid communities, 43
42. An herb dominates vascular cover.....................................................................	67

Graminoid Communities
43. Alkaligrass (Puccinellia spp.) dominates on tidally-influenced wetlands..	Alkali grass
43. Alkaligrass absent..............................................................................................	44
44. Beachrye dominates at the beach storm-line.................................................	Beachrye
44. Beachrye absent................................................................................................	45
45. Circumpolar reedgrass (Calamagrostis deschampsoides) dominates on tidally-influenced wetlands......................................................................................	Circumpolar reedgrass – Pacific silverweed
45. Circumpolar reedgrass absent..........................................................................	46
46. Lyngbye’s sedge (Carex lyngbyei ) dominates vascular cover.....................	47
46. Lyngbye’s sedge not dominant.......................................................................	48
47. Water horsetail cover > 2%.............................................................................	Lyngbye’s sedge – Water horsetail
47. Water horsetail absent.......................................................................................	Lyngbye’s sedge
48. Ramensk’s sedge (Carex ramenskii ) dominates vascular cover (Lyngbye’s sedge frequently present......................................................................	Ramensk’s sedge
48. Ramensk’s sedge absent.................................................................................	49
49. Bluejoint dominates vascular cover..................................................................	Bluejoint Communities, 50
49. Bluejoint absent, or only a few stems...............................................................	52
50. Bluejoint present with a uniform field horsetail understory.......................	Bluejoint – Field horsetail
50. Field horsetail cover low, or not present......................................................	51
51. An island floating on a lake (rare).....................................................................	Bluejoint floating island
51. Alongside a stream, often with a diverse assemblage of herbs.....................	Bluejoint streamside
52. Tufted bulrush (Trichophorum caespitosum) the dominant vascular plant............................................................................................................................	Tufted bulrush communities, 53
52. Tufted bulrush not present, or only as scattered clumps..............................	56
53. Tall cottongrass (Eriophorum angustifolium sens. lat.) the next most abundant vascular plant.............................................................................................	Tufted bulrush - Tall cottongrass
53. Another graminoid next most abundant............................................................	54
54 Few-flower sedge the next most abundant vascular plant..............................	Tufted bulrush – Fewflower sedge
54. Another graminoid next most abundant..........................................................	55
55. Alpine bulrush (Trichophorum alpinum) the next most abundant vascular plant............................................................................................................................	Tufted bulrush – Alpine bulrush
55. Tufted hairgrass the next most abundant vascular plant..................................	Tufted bulrush – Tufted hairgrass
56. Tall cottongrass (Eriophorum angustifolium sens. lat.) present (with little or no tufted bulrush)........................................................................................	57
56. Tall cottongrass absent, or only a few stems.................................................	59
57. Livid sedge (Carex livida ) also present; more than a few plants...................	Tall cottongrass – Livid sedge
57. Livid sedge , if present, only as a few stems.....................................................	58
58. Fewflower sedge (Carex pauciflora ) common, frequently more abundant that tall cottongrass ..................................................................................	Fewflower sedge - Tall cottongrass
58. Fewflower sedge absent, or only a few clumps; few other vascular plants present at much more than 1% cover; Sphagnum spp. cover typically near 100%..........................................................................................................................	Sphagnum moss – Tall cottongrass
59. Fewflower sedge dominates with common tufted hairgrass clumps.............	Fewflower sedge - Tufted hairgrass
59. Other sedges dominant; tufted hairgrass absent, or only a few clumps.........	60
60. Water sedge (Carex aquatilis ) dominates vascular cover over a marsh fivefinger (Comarum palustre ) ground layer........................................................	Water sedge / Marsh fivefinger
60. If water sedge dominates, then few other vascular plants are present at much more than 1% cover; or water sedge is absent, or only a few stems.........	61
61. Water sedge dominates, with few other herbs or graminoids, though dwarf birch and/or crowberry may be common................................................................	Sphagnum moss – Water sedge
61. Water sedge not present, or only a few stems.................................................	62
62. Sphagnum moss (Sphagnum spp.) dominates; little or no standing water present........................................................................................................................	63
62. Standing water present, a sedge dominates with an herb...............................	66
63. Red cottongrass (Eriophorum russeolum ) dominates with sphagnum moss...........................................................................................................................	Sphagnum moss – Red cottongrass
63. A sedge (Carex spp.) dominates with sphagnum.............................................	64
64. Creeping sedge (Carex chordorrhiza ) and often standing water dominate with or without sphagnum moss..............................................................	Sphagnum moss – Creeping sedge
64. Creeping sedge and standing water typically absent, or not common..........	65
65. Manyflower sedge (Carex pluriflora ) the dominant sedge...........................	Sphagnum moss - Manyflower sedge
65. Round sedge (Carex rotundata ) the dominant sedge.....................................	Sphagnum moss – Round sedge
66. Beaked sedge (Carex utriculata ) dominates with water horsetail ..............	Beaked sedge – Water horsetail
66. Mud sedge (Carex limosa ) dominates with buckbean (Menyanthes trifoliata )...................................................................................................................	Mud sedge – Buckbean

HERBACEOUS COMMUNITIES
67. Tidally-influenced communities.......................................................................	68
67. Community not influenced by periodic tidal inundation.................................	70
68. Goosetongue (Plantago maritima ) dominates vascular cover....................	Goosetongue
68. Another plant dominates..................................................................................	70
69. Slender glasswort (Salicornia maritima) dominates vascular cover............	Slender glasswort
69. Seaside arrowgrass (Triglochin maritima) dominates, usually with marsh arrowgrass (Triglochin palustris)..........................................................................	Marsh Arrowgrass – Seaside arrowgrass
70. Buckbean emergent from open water; few other plants present..................	Buckbean
70. Calla (Calla palustris) dominates with water horsetail ...............................	Calla – Water horsetail

Cook Inlet Wetlands

Plant Communities

Key to the Wetland Plant Communities of the Kenai Lowlands