Skagit River Cottonwoods Overview

Posted March 14, 2000 | Categories : 89,Rare Species,Reports,Species List |


The reserve is on the floodplain of the Skagit River , a relatively small, fast-flowing river with a gradient of about six m/km. The northeast-southwest trending valley, located in the Hozameen Ranges of the Cascade Mountains, is bounded by slopes of about 30o which rise to peaks of 2100-2500 m. The valley is relatively straight, the river slightly sinuous within its narrow floodplain. Bedrock is of the Hozameen series, made up of Cretaceous sediments and much volcanic material. Upon retreat of Pleistocene glaciers an accumulation of poorly sorted debris was left behind. This has been resorted by the Skagit River and tributary streams to form the present alluvial valley bottom deposits. Soils have not been described. Talus slopes border part of the reserve on its west side. Climate is transitional between that of the wet coast and dry interior.

See the complete PDF file from  BCParks: Skagit River Cottonwoods ER 89


Black cottonwood trees at this site are mostly in mixed stands containing conifers, including western redcedars up to two metres in diameter, and some Douglas-fir, grand fir, and bigleaf maple. Douglas-fir-western redcedar stands occur on the fan of Marmotte Creek, and Douglas-fir is the characteristic tree of the lower mountain slopes. The shrubs red-osier dogwood, hazelnut, thimbleberry and salmonberry are common in the floodplain forest understory, together with sword fern. Other trees recorded in this area are amabilis fir, Engelmann spruce, western white pine and western hemlock.
The fauna has not been surveyed. Rainbow Trout, Dolly Varden Char and Eastern
blue-curls, mountain (Trichostema oblongum)
cottonwood, black (Populus trichocarpa ssp. trichocarpa)
dogwood, red-osier (Cornus stolonifera)
Douglas-fir (Pseudotsuga menziesii)
elmera (Elmera racemosa var. racemosa)
fern, lace (Cheilanthes gracilima)
fern, sword (Polystichum munitum)
fir, amabilis (Abies amabilis)
fir, grand (Abies grandis)
hazelnut, beaked (Corylus cornuta)
hemlock, western (Tsuga heterophylla)
maple, bigleaf (Acer macrophyllum)
pine, western white (Pinus monticola)
redcedar, western (Thuja plicata)
salmonberry (Rubus spectabilis)
spruce, Engelmann (Picea engelmannii)
hazelnut, beaked (Corylus cornuta)
steer’s head (Dicentra uniflora)
thimbleberry (Rubus parviflorus var. parviflorus)

Dolly Varden (Salvelinus malma)
Owl, Spotted (Strix occidentalis)
Trout, Brook (Salvelinus fontinalis)
Trout, Rainbow (aka Steelhead) (Oncorhynchus mykiss)