Soils of the - Agriculture and Agri-Food Canada

ELPHINGSTONE SOILS (EF)
Location and Extent : Elphingstone soils occur only in small, scattered areas in the mountainous, norther n
part of the map area . Only 25 ha of pure map units and 40 ha of soil complexes dominated by Elphingstone soil s
are classified . The complexes are with Sayres and Whonnock soils .
Topography and Elevation : Elphingstone soils vary in topography from depressional to moderatel y
sloping or gently rolling with slopes less than 8 percent . They are found in areas that are depressional in relatio n
to adjacent soils or on lower, seepage and runoff receiving areas . Mostly they occur between 300 and 1200 m
above sea level .
Parent Material and Texture : Elphingstone soils have developed from partially decomposed organi c
deposits which are composed mainly of sedge, reed and grass remains as well as some wood . The organic
deposits, between 40 and 160 cm thick, overlie mainly glacial till or sometimes, alluvium . The surface is usuall y
poorly decomposed (fibric) while the subsurface and subsoil organic material is partly decomposed (mesic) .
The underlying mineral soil is gravelly sandy loam or gravelly loam and in some areas, particularly near strea m
channels, thin lenses and strata of silty or sandy mineral material sometimes occur in the organic deposits .
Soil Moisture Characteristics : Elphingstone soils are very poorly drained . They are moderately perviou s
and have very high water holding capacities and slow to moderate surface runoff . The watertable is at or nea r
the surface for most of the year due to accumulating seepage and runoff from higher, adjacent areas . At th e
higher elevations snow remains until late spring .
General Soil Description : Elphingstone soils have a surface organic layer, about 10 to 20 cm thick that i s
dark reddish brown to yellowish-brown and consists mainly of relatively undecomposed sedge, reed and gras s
remains . This is underlain by about 70 cm of dark reddish brown to yellowish-brown, matted to massive, firm ,
organic material containing variable amounts of woody fragments . This zone then grades to about 10 cm o f
black, well-decomposed organic material which is massive, firm and sometimes cdntains a proportion of silty o r
sandy mineral soil material . Underlying this is firm, massive, greenish-gray or brownish-gray, gravelly minera l
soil containing occasional reddish mottles . Soil reaction grades from extremely acid in the surface to strongly o r
medium acid in the underlying mineral soil . Soil classification is Terric Mesisol .
Commonly Associated Soils : Sayres and Whonnock soils commonly are found in close association wit h
Elphingstone soils . Both differ from Elphingstone soils by being mineral rather than organic in composition .
Both are also well to imperfectly drained and additionally, Sayres soils have bedrock within 100 cm of the soi l
surface .
Vegetation : The vegetation on Elphingstone soils consists mainly of reeds, sedges and grasses with som e
willow, yellow cedar (western red cedar at the lower elevations), western and/or mountain hemlock, and Pacifi c
silver fir as well as a variety of herbaceous shrubs and herbs . Rooting is restricted to the upper 70 cm or less b y
the high watertables .
General Land Use Comments : (1) Elphinstone soils are not used for agriculture at the present time . Poo r
drainage (and sometimes flooding) as well as adverse climate (high elevations) generally limit these soils t o
potential pasture or forage uses . Under natural conditions they provide native pasture which is utilized by
wildlife . (2) Limitations similar to those for agriculture as well as low bearing strengths make these soils unsuite d
for urban or similar uses . (3) Forest productivity is very low.
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