11.0 NON-FORESTED SUBALPINE AND ALPINE ECOSYSTEMS
Typically a high elevation, northern, grassland habitat, characterized by lush bunchgrass growth, with forbs, sedges and terrestrial lichens.
This unit is only found in the alpine tundra (AT) zone in most of the mountain ranges in the province.
The vegetative cover is lush and grass-dominated. Altai fescue and mountain sagewort dominate these alpine grasslands. Bellard's kobresia, alpine sweetgrass, one-headed pussytoes, mountain harebell, glaucous gentian, spiked woodrush, diverse-leaved cinquefoil and small-awned sedge are common secondary alpine grassland species.Terrestrial lichens dominate the moss and lichen layer, including ragged snow, curly snow, common coral and reindeer lichens. Awned haircap moss is also common in this moderately developed layer.
Occurs on gentle to steep slopes in the alpine tundra zone. Submesic to mesic, well-drained colluvial or morainal materials are typical. Discontinuous snow cover may occur in the winter due to strong winds.
Typically a high elevation dwarf shrubland habitat, characterized by cold resistant vegetation, consisting of mountain-heathers, forbs, graminoids and lichens.
This unit is only found in the alpine tundra (AT) zone in most of the mountain ranges in the province.
Dwarf shrubs dominate this community; four-angled mountain-heather, dwarf snow willow, polar willow, white mountain-heather, mountain-avens, bog blueberry, partridgefoot and lingonberry are most common. Small-awned sedge, altai fescue, mountain sagewort, moss campion, capitate lousewort, glaucous gentian, alpine bistort and arctic bluegrass are commonly found intermixed with the dwarf shrubs. A sparse to moderate moss and lichen layer is typically composed of awned haircap moss and broom moss, as well as common coral, Cetraria, Cladonia and Peltigera lichens.
White and yellow mountain-heathers dominate the dwarf shrub layer, with minor amounts of pink mountain-heather and partridgefoot also present. Small-awned sedge, black alpine sedge, woolly pussy-toes, altai fescue, mountain arnica, slender hawkweed, glaucous gentian and subalpine daisy are commonly found intermixed with these dominant dwarf shrub species. A sparse to moderate moss and lichen layer is typically composed of haircap juniper moss and pale-stalked broom moss, as well as Cetraria, chocolate chip and orange-foot Cladonia lichens.
Dwarf shrubs including four-angled mountain-heather, white mountain-heather, pink mountain-heather, yellow mountain-heather and dwarf willows dominate this alpine plant community. Partridgefoot, woolly pussytoes, small-awned sedge, black alpine sedge, altai fescue, mountain arnica, mountain sagewort and subalpine daisy are commonly found intermixed with these dominant dwarf shrub species. A sparse to moderate moss and lichen layer is typically composed of haircap moss and broom moss, as well as Cetraria, Cladonia and Peltigera lichens.
Typically occurs on moist to mesic sites, often moisture receiving; with gentle to steep, cool aspects where there is greater snow accumulation and duration. Soils are typically imperfectly to well drained, deep, medium- to coarse-textured colluvial, morainal or fluvial materials.
Some heath communities are situated on warmer aspects, but maintain similar plant communities.
Typically a high elevation, herbaceous community, dominated by moisture-loving forbs and/or sedges, on wetter sites in alpine areas.
This unit is only found in the alpine tundra (AT) zone in most of the mountain ranges in the province.
Typically dominated by a dense cover of sedges, including small-awned sedge and black alpine sedge; altai fescue, alpine fescue, arctic woodrush, rushes, dwarf snow willow and arctic willow are also abundant. Alpine timothy, western pasqueflower, bluegrasses, Sitka valerian, sibbaldia, cottongrass and common horsetail are often associated herbaceous species. A sparse to moderate moss and lichen layer is typically composed of snow lichen, common coral lichen, Icelandmoss, reindeer lichen, golden fuzzy fen moss, glow moss and haircap moss.
Typically, forbs dominate these alpine meadow communities, including western pasqueflower, arrow-leaved groundsel, Sitka valerian, arctic lupine, mountain arnica and subalpine daisy. Dwarf snow willow, polar willow, yellow glacier lily, Indian hellebore, sedges, subalpine buttercup and mountain arnica are commonly associated with this community. A sparse moss and lichen layer composed of golden fuzzy fen moss, glow moss, haircap moss and snow lichens, is characteristic.
Typically situated on gently to moderately sloping seepage sites; lower alpine receiving areas are most common. Seepage is often provided by snow accumulations, on these mesic to subhygric sites. The soils are characteristically moderately well to imperfectly drained, deep or shallow colluvial or morainal veneers.
A short growing season and high snow accumulation results in few areas suitable for extensive vegetative growth in much of the alpine region.
Typically situated on gently to moderately sloping seepage sites; middle to high alpine receiving areas are most common. Seepage is often provided by snow accumulations within cirque bottoms and at the base of slopes. The soils are characteristically moderately well to well drained, deep colluvial or morainal veneers.
A short growing season and high snow accumulation results in few areas suitable for extensive vegetative growth in much of the alpine region.
Globeflower, yellow-marsh marigold, fringed grass-of-parnassus, horsetail and cowparsnip are often associated with slightly wetter alpine meadows.
More northerly locations may have a greater amount of dwarf snow willow and polar willow present, often codominating with sedge and forb species.
Typically a high elevation, sparsely vegetated habitat, characterized by a mixture of rocky slopes and a sparse cover of grasses, lichens and low shrubs.
This unit is only found in the alpine tundra (AT) zone in most of the mountain ranges in the province.
Typically the vegetation covers less than 5% of the surface and is limited to small pockets of soil and moisture accumulation.
The remainder of these units are composed of barren rock/rubble and areas with no, or very shallow soils. The shrub layer is poorly developed and limited to dwarf willows and mountain-avens. Moss campion, saxifrage, arctic bluegrass, small-awned sedge and altai fescue are often found scattered throughout these units. The rocky, exposed areas are dominated by a variety of lichen species; rock orange lichen, rocktripe lichen, green map lichen and curly snow lichen are abundant.
Typically vegetated sites are very xeric to xeric. The soils are generally lacking or very shallow with extremely poor nutrient availability.
The alpine tundra experiences extremely short growing seasons, followed by periods of very high snowfall. However, sites may be totally snowfree due to high winds and/or the steepness of the slope. The processes of solufluction and frost-heaving commonly occur where soils are present. All are factors limiting the establishment of vegetation.
Typically a high elevation, northern, shrubland habitat, characterized by a dense cover of deciduous shrubs with graminoids, forbs and terrestrial lichens.
This unit is only found in the alpine tundra (AT) zone in most of the mountain ranges in the province.
Willows and scrub birch dominate these dense shrub communities. Shrubby cinquefoil and bog blueberry are commonly found in these communities as well. Crowberry, altai fescue, alpine fescue, arctic lupine, arctic bluegrass, small-awned sedge, mountain sagewort, lingonberry, and woodrush can be found in the moderate herb layer. The bryoid community is dominated by golden fen fuzzy moss, along with secondary species including step and ragged mosses. Curly snow lichen, reindeer lichen and coral lichen are often found on these sites as well.
Wetter, gently sloping alluvial fans found in alpine valley bottoms are often dominated by shrub communities. Barratt's willow is characteristically dominant, with felt-leaved, Alaska and grey-leaved willow commonly present as secondary species. The herbaceous layer is usually composed of a variety of species including, common horsetail, sedges, bluejoint, sweet colts-foot, dwarf nagoonberry, tall Jacob's-ladder and tall bluebell. Golden fuzzy fen moss dominates the moss and lichen layer, secondary species include, step moss, sickle moss, ragged moss and Calliergon spp., as well as freckled lichen.
Typically sites are located on mesic to moist, colluvial and morainal blankets or veneers, or glaciofluvial undulating materials. Sites range from lower receiving positions to upper exposed areas.