Soils of the - Agriculture and Agri-Food Canada

HARRISON SOILS . (HR)
Location and Extent : Harrison soils occupy scattered, lower elevation areas, mainly in the eastern part of th e
map area north of the Fraser River. There are about 610 ha of pure map units and 270 ha of soil complexe s
dominated by Harrison soils . The complexes are mainly with Isar and Shalish soils .
Topography and Elevation : The topography of Harrison soils is mostly moderately to steeply slopin g
although gently or very steeply sloping areas also occur. Slope gradients range from 5 to 30 percent an d
elevations vary between 20 and 175 m above sea level .
Parent Material and Texture : Harrison soils have developed from coarse to moderately coarse textured ,
usually stony, alluvial fan deposits, commonly with a shallow capping of silty, eolian material mixed into the
surface . Surface textures are mainly gravelly sandy loam, gravelly loam or loam grading to gravelly sand o r
sandy gravel in the subsurface and subsoil .
Soil Moisture Characteristics : Harrison soils are generally well to rapidly drained, with small areas alon g
some fan aprons being moderately well drained . They are rapidly pervious and have low water holding capacit y
and slow surface runoff .
General Soil Description : Harrison soils generally have a thin (usually less than 5 cm), surface organi c
layer consisting of raw to well-decomposed forest litter. This is underlain by a discontinuous, grayish, leached ,
sandy layer less than 3 cm thick . In turn, this is abruptly underlain by about 20 cm of friable, loamy or sand y
material which is dark brown to reddish-brown in colour and contains variable amounts of gravels and stones ,
and a few, fine, spherical concretions . This zone grades to unweathered, loose gravelly sand or gravel at abou t
40 cm . Soil reactions vary from very strongly acid in the upper part of the soil to moderately acid in the subsoil .
Soil classification is Orthic Humo-Ferric Podzol.
Commonly Associated Soils : Isar, Elk and Shalish soils are often closely associated with Harrison soils .
Isar soils differ from Harrison soils by having little soil development (are regosolic) while Elk soils differ by bein g
poorly drained and having black surfaces . Shalish soils differ by having strongly cemented subsoil layers .
Vegetation : Small areas are cleared and cultivated . Uncleared areas support second-growth coast Douglasfir,
western red cedar, some western hemlock, red alder, bigleaf and vine maple and birch as well a s
huckleberry, thimbleberry, salal and bracken . Rooting is generally unrestricted except for moderate limitation s
imposed by coarse, stony subsoil textures .
General Land Use Comments : (1) Harrison soils have limited agricultural use because of droughtiness ,
stoniness and adverse topography. Irrigation and stone-picking improves their value for forage, pasture an d
other crops . (2) Urban and similar uses are moderately suited to these soils . The soils have high bearin g
strength and good drainage . Excessive stoniness in the subsoil may cause problems in excavating basement s
and underground utilities while adverse topography may be limiting in some areas . Efficient septic tank effluent
disposal occurs although incomplete filtration by the coarse subsurface textures may lead to ground wate r
contamination . Harrison soils are also potential sources of aggregate . (3) Forest growth is moderately goodabout
9 to 12 m 3/ha/yr of wood production by coast Douglas-fir is indicated from limited plot data .
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