Skwaha ER Overview: Physical and Biological

Posted June 13, 2000 | Categories : 88,Reports,Species List |


The reserve is near theis near the southern end of the Clrear Range which occupies the “V”  between the Thompson and Fraser rivers, north of Lytton. The reserve has two major landforms, a rolling summit above the 1650 m elevation in the north, and steep valley slopes in the south. The predominant aspect is south and southwest. Soils are primarily Brunisols, characteristic of moderately open coniferous forest zones. Drainage is entirely via small tributaries of Skoonka Creek, eastward into the Thompson River. The climate is moderately dry due to the rain-shadow effect of the Coast Ranges, however, precipitation increases markedly with elevation and considerable snow accumulates in the summit area.

See the full PDF from BC parks:Skwaha Lake ER 88


Variations in elevation, exposure, soil moisture and fire history result in a very complex mosaic of mature forest, burned forest and meadows in this reserve. The tree cover here, over an elevational range of only 600 m, contains such ecologically diverse elements as scattered ponderosa pine trees and subalpine fir stands. Grass-forb meadows, many with spectacular wildflower stands, are widespread at lower and middle elevations as a result of the generally dry climate, southerly exposure and occurrence of wildfire. Large alpine-subalpine meadows also occur in a parkland setting among subalpine forest stands on the summit.
The Douglas-fir Zone, with an understory of pinegrass, occurs primarily below the
1500 m elevation at the lower fringe of the reserve, and contains a few scattered ponderosa pine trees and aspen groves. The Montane Spruce Zone, characterized by Engelmann spruce-lodgepole pine stands, is mostly between the 1525 and 1675 m levels, while the Engelmann Spruce-Subalpine Fir Zone is restricted to the summit area, primarily above the 1675 m elevation. Burned forests, at various elevations in the eastern half of the reserve, are largely dominated by juvenile lodgepole pine.
Eight meadow communities have been described and mapped, four within the Interior Douglas-fir and Montane Spruce zones and four in the subalpine area. The lowest elevation meadows, usually on moderate south-facing slopes, are dominated by an association of arrow-leaved balsam-root and grasses, the dominant grass on grazed sites being Kentucky bluegrass, that on ungrazed sites bluebunch wheatgrass. Acres of densely packed balsam-root plants, together with less abundant species like common red paintbrush and upland larkspur, present a spectacular sight during the peak of flowering. These meadows give way with increasing elevation to the pinegrass-balsamroot community. At middle to upper elevations, two other communities dominated by pinegrass also occur.
The most extensive subalpine meadows are dominated by Indian hellebore, cow- parsnip and arctic lupine but include other showy species like Sitka valerian, western and arrowleaved groundsel and glacier lily. Less extensive moist, subalpine meadows support sharptooth angelica-western groundsel and Sitka valerian-Indian hellebore-globeflower communities. On exposed subalpine ridges, a community complex characterized by thread-leaved sandwort has been  recognized in which associate4d species include pusseytoes, old man’s whiskers, Rocky Mountain fescue, balsamroot and pinegrass.
To date, 273 species of vascular plants have been recorded in this reserve, of which at least 16 are rare in British Columbia. Rare plants include alpine- wintergreen, Hooker’s Onion, large-flowered tritalea, white tritales,Raynold’s sedge, alpine indian paintbrush,mountain lady’s slipper, many flowered hackelias, blue hackelia, Nuttall’s sunflower, little sunflower, Fendler’s waterleaf, alpine lewisia and purple onion grass.
The reserve provides excellent summer range for mule deer, and for a herd of Rocky Mountain bighorn sheep which was introduced to the Spences Bridge area. Coyotes and black bears have been noted. Horned larks and waterpits are common in alpine areas. Other birds recorded here include the blue grouse, golden eagle, red-tailed hawk, pileated woodpecker, common flickre. Clsark’s nutcracker, gray jay, Steller’s jay red ␣crossbill and several species of warblers, chickadees and sparrows.


Significant Species:

Bighorn Sheep —-Blue listed
curly sedge —-Blue listed
Fendler’s waterleaf
Geyer’s onion —-Blue listed
Great Basin nemophila
Hooker’s Onion
large-flowered triteleia

Nutthall’s sunflower —-Redlisted
oniongrass —-Redlisted
purple oniongrass —-Blue listed
Raynold’s sedge
white triteleia