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NATURALIST'S GUIDE TO THE AMERICAS 



Columbia red-backed vole (Evotomys 

 g. saturatus} ; Rocky Mountain vole 

 (Microtus mordax mordax}', British Co- 

 lumbia muskrat (Fiber z. osoyoosensis) ; 

 Rocky Mountain jumping-mouse (Zapus 

 princeps) ; Okanagan marmot (Marmota 

 c. okanagana) ; northern mantled ground- 

 squirrel (Callospermophilus I. tescorum) ; 

 Canadian mountain chipmunk (Euta- 

 mias amoenus ludibundus) ; Streator's 

 red squirrel (Sciurus h. streatori); 

 British Columbia snowshoe hare (Lepus 

 a. columbiensis) ; Rocky Mountain pika 

 (Ochotona princeps} ; bighorn sheep (Om 

 canadensis}] Rocky Mountain goat 

 (Oreamnos montanus}} mule deer (Odo- 

 coileus hemionus')', mountain caribou 

 (Rangifer montanus) . Some of the more 

 notable of the birds are the following: 

 dusky grouse, Franklin's grouse, Canada 

 ruffed grouse, red-necked sapsucker, 

 western piliated woodpecker, Rocky 

 Mountain jay, Clark's nutcracker, long- 

 tailed chickadee, Louisiana tanager, 

 red-eyed vivio, Audubon's waibler, 

 mountain chickadee, Hudsonian chick- 

 adee, willow thrush, olive-backed 

 thrush, and mountain bluebird. 



D. ALPINE REGIONS 



Alpine conditions are to be found on 

 most of the British Columbia moun- 

 tains above an altitude of 5500 ft., 

 especially on those mountains situated 

 within the "wet belts" where the pre- 

 cipitation ensures an abundant snowfall 

 during winter. 



At an altitude of 4500 ft., is found 

 moist meadow-like land containing much 

 humus, and abounding in ericaceous 

 shrubs such as White Rhododendron 

 (R. albiflorum) ; red heather (Phyllodoce 

 empetriformis") ; creamy yellow heather 

 (P. glanduliflorus) } white heather (Cas- 

 siope Mertensiana}} copper-bush (Cla- 

 dothamnus pyrolceflorus) , blue-berries 

 (V actinium, various species). Much 

 of the moist land is carpeted with the 

 beautiful alpine Spiraea (Eriogynia 

 pectinata) so frequently mistaken for 

 a saxifrage, associated with marsh mari- 

 gold (Caltha leptosepala} ; globe flower 

 (Trollius albiflorus), and numerous 



saxifragaceous plants. In this zone 

 small subalpine lakes are abundant. 

 These are frequently stocked with yel- 

 low water lilies (Nuphar polysepalum) ; 

 while spongy Sphagnum areas in the 

 vicinity have mountain laurel (Kalmia 

 polifolia) ; gentians (G. sceptrum) ; grass 

 of Parnassus (Parnassia palustris}\ 

 deer cabbage, and bogbean (Menyanthes 

 crista-galli and M. trifoliata) . This 

 subalpine association ranges, according 

 to locality, from 4000 ft. altitude to 

 approximately 6000 ft. At the former 

 elevation the supply of moisture is 

 maintained by seepage from the melting 

 snow in the adjacent wooded slopes; 

 at the latter elevation, seepage is from 

 the snowfields or glaciers on the exposed 

 mountain sides, timber line ranging in 

 the "wet belts" from 5500 ft. to approxi- 

 mately 6500 ft. altitude. Here, the 

 last trees are alpine fir, white bark pine 

 (Pinus albicaulis') , and mountain hem- 

 lock, all of which are low and stunted, 

 forming dense tangle thickets from 1 

 to 3 ft. high, the older trees often spread- 

 ing over a large area, due chiefly to the 

 great weight of snow which buries 

 them for the greater part of the year. 

 The snowfall during the winter, at that 

 altitude varies from 30 to 50 ft. in depth. 



The soil of the Arctic Alpine belt 

 (Arctic-alpine zone) contains little 

 humus, and is largely composed of silt 

 from the weathered rocks. The type 

 of vegetation varies in accordance with 

 this soil, whether formed from rocks 

 of sedimentary or volcanic origin; the 

 latter, as a rule, producing the greatest 

 variety of species. 



The characteristic plants of this belt 

 are moss campion (Silene acaulis}} 

 northern wormwood (Artemisia norve- 

 gica var. pacifica) ; silky phacelia (P. 

 serica); Douglas' Phlox (P. Douglasii); 

 crowberry (Empetrum nigrum) ; creeping 

 Azalea (Loiseleuria procumbens) ; blue- 

 green gentian (Gentiana glauca); west- 

 ern Anemone (A. occidentalis) ; Tolmie's 

 saxifrage (S. Tolmiea'), often growing 

 within a few feet of glaciers, and many 

 other low growing tufted flowering 

 plants. 



