The taxonomy and distribution of Festuca idahoensis in British Columbia and northwestern Washington

1983 ◽  
Vol 61 (1) ◽  
pp. 345-353 ◽  
Author(s):  
Leon E. Pavlick
Keyword(s):  
British Columbia ◽  
Leaf Morphology ◽  
Ecological Distribution ◽  
Cascade Mountains ◽  
Festuca Idahoensis

Plants of Festuca idahoensis from west of the Cascade Mountains in British Columbia and northwestern Washington differ in their leaf morphology and panicle size from those east of the Cascade Mountains. The western plants are recognized as F. idahoensis var. roemeri. The geographic and ecological distribution of the species and a key for distinguishing the two varieties are given.

scholarly journals Full-depth avalanche occurrences caused by snow gliding, Coquihalla, British Columbia, Canada

1999 ◽  
Vol 45 (151) ◽  
pp. 539-546 ◽  
Author(s):  
Jennifer Clarke ◽  
David McClung
Keyword(s):  
British Columbia ◽  
Stainless Steel ◽  
Ground Surface ◽  
Free Water ◽  
Important Influence ◽  
Reliable Indicator ◽  
Climate Data ◽  
Cascade Mountains ◽  
Sloping Ground ◽  
Snow Gliding

AbstractSnow glide is the translational slip of the entire snowpack over a sloping ground surface, and it is thought that rapid rates of snow glide precede full-depth avalanches. The nature of avalanches that release at the ground makes them difficult to predict and difficult to control using explosives.On-slope instrumentation comprised of stainless-steel "glide shoes" was used to measure rates of snow glide for two winters on a bedrock slope adjacent to the Coquihalla Highway, Cascade Mountains, British Columbia, Canada. Climate data and avalanche occurrences were recorded by the British Columbia Ministry of Transportation and Highways.Our results show that the supply of free water to the snow/ground interface by rain or snowmelt is the most important influence on full-depth avalanche release. Full-depth avalanche release responds to rainfall and snowmelt events within 12-24 hours. Occasionally, full-depth avalanches occur unexpectedly during clear, cold periods. Snowmelt by radiation is thought to contribute enough meltwater during these cold periods to induce higher rates of snow glide and full-depth avalanche release. The results also indicate that snow glide alone is not a reliable indicator for full-depth avalanche release.

Coquitlam Drift: a pre-Vashon Fraser glacial formation in the Fraser Lowland, British Columbia

1981 ◽  
Vol 18 (9) ◽  
pp. 1443-1451 ◽  
Author(s):  
Stephen R. Hicock ◽  
John E. Armstrong
Keyword(s):  
British Columbia ◽  
Glacial Maximum ◽  
Cascade Mountains ◽  
Short Pulses ◽  
Coast Mountains ◽  
The North ◽  
Glaciomarine Sediments

Coquitlam Drift is formally defined and stratotypes established for it in the Coquitlam – Port Moody area, B.C. It is a Pleistocene formation consisting of till, glaciofluvial, ice-contact, and glaciomarine sediments deposited between 21 700 and 18 700 years BP, during the Fraser Glaciation (late Wisconsin) and prior to the main Vashon glacial maximum at about 14 500 years BP. The drift was deposited in short pulses by valley and piedmont glaciers fluctuating into the Fraser Lowland from the Coast Mountains to the north and Cascade Mountains to the east.

Holocene Treeline and Climate Change in the Subalpine Zone near Stoyoma Mountain, Cascade Mountains, Southwestern British Columbia, Canada

2000 ◽  
Vol 32 (1) ◽  
pp. 73-83 ◽  
Author(s):  
Marlow G. Pellatt ◽  
Michael J. Smith ◽  
Rolf W. Mathewes ◽  
Ian R. Walker ◽  
Samantha L. Palmer
Keyword(s):  
Climate Change ◽  
British Columbia ◽  
Cascade Mountains ◽  
Subalpine Zone

Mid-Tertiary volcanic rocks of the Cascade Mountains, southwestern British Columbia, ages and correlations

1981 ◽  
Vol 18 (3) ◽  
pp. 662-664 ◽  
Author(s):  
W. H. Mathews ◽  
R. G. Berman ◽  
J. E. Harakal
Keyword(s):  
British Columbia ◽  
Late Miocene ◽  
Volcanic Rocks ◽  
Early Miocene ◽  
Chemical Data ◽  
Volcanic Centre ◽  
Calc Alkaline ◽  
Cascade Mountains

Potassium–argon dates and chemical data have been obtained from three mid-Tertiary volcanic centres in the Hope area of the Cascade Mountains, southwestern British Columbia. Two of these, the Coquihalla volcanic centre and the Podunk Creek body, prove to be of early Miocene age (ca. 22 Ma), whereas the Skagit Formation is mid- to late Miocene (ca. 12.5 Ma). All three bodies are calc-alkaline.

Northern Cascade-Fraser River, Domain 7

2007 ◽  
Author(s):  
Earl B. Alexander ◽  
Roger G. Coleman ◽  
Todd Keeler-Wolfe ◽  
Susan P. Harrison
Keyword(s):  
British Columbia ◽  
Fault System ◽  
San Juan ◽  
Fraser River ◽  
Cascade Mountains ◽  
River Flows ◽  
San Juan Islands ◽  
The North ◽  
North American Craton ◽  
Cordilleran Ice Sheet

The Northern Cascade–Fraser River domain conforms to the Northern Cascade Mountains physiographic province in northwestern Washington and southern British Columbia, the San Juan Islands between the southern tip of Vancouver Island and the Northern Cascade Mountains, and much of the Interior Plateau province of British Columbia. The thread that connects these areas is the north–south Straight Creek–Fraser River fault system that runs through the Northern Cascade Mountains and northward along the Fraser River. The localities of domain 7 are along faults that branch off from this major fault system. The Northern Cascade Mountains are indeed mountainous, and the Interior Plateau of British Columbia is an area of dissected plateaus and scattered mountains. The Fraser River flows northwest in the Rocky Mountain Trench, which separates the North American craton on the northeast from accreted terranes on the southwest; then it turns around the northwest end of the Cariboo Mountains to the Interior Plateau. In the Interior Plateau, the Fraser River flows from Prince George south about 500 km to the Northern Cascade Mountains before turning westward toward the Pacific Coast. The northern part of domain 7 is in that part of the Fraser River basin, including tributaries northwest of Prince George, which is in the Interior Plateau province. Low, hilly terrain dominates the San Juan Islands. All of these areas in domain 7, except the Ingalls complex on southeast margin of the Northern Cascade Mountains, were covered by the Cordilleran ice sheet during the last stage of the Pleistocene glaciation, leaving <15 ka years for soil development on the current ground surfaces. Although alpine glaciers formed in the southeastern margin of the Northern Cascade Mountains, they did not cover all of the soils, allowing some of them longer time for development. Elevations in domain 7 range from sea level on San Juan Islands to mostly in the 600–1500 m range on the Interior Plateau of British Columbia, and up to 4392 m on Mt. Rainier in the Northern Cascade Mountains.

Isozyme variation in Pinusmonticola

1983 ◽  
Vol 13 (6) ◽  
pp. 1122-1132 ◽  
Author(s):  
R. J. Steinhoff ◽  
D. G. Joyce ◽  
L. Fins
Keyword(s):  
British Columbia ◽  
Sierra Nevada ◽  
Species Distribution ◽  
Allelic Frequency ◽  
Isozyme Variation ◽  
Cascade Mountains ◽  
South Central ◽  
Expected Heterozygosity ◽  
Transition Area ◽  
Oregon Cascades

Seeds from 28 stands representing most of the range of Pinusmonticola Dougl. were analyzed for electrophoretically demonstrable variation in 10 proteins encoded by 12 genetic loci. On the average, 65% of the loci per stand were polymorphic, and expected heterozygosity of offspring was 18%. The populations could be assigned to two geographic groups, a broad northern one and a rather restricted southern one. The southern group consisted of populations from the Sierra Nevada and southern Cascade Mountains in northern California and from the Warner Mountains in south-central Oregon. These southern populations were similar to each other but all differed from those of the northern group in allelic frequency patterns for several isoenzymes. Across the northern part of the species' distribution (British Columbia, Washington, northern Oregon, Idaho, and Montana) differences among stands were minor and essentially random. Collections from stands in the central and southern Oregon Cascades and the Siskiyou Mountains of northwestern California were more nearly like the northern stands but exhibited some characteristics indicative of a transition area between the Sierra and northern types.

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