Soils of the - Agriculture and Agri-Food Canada

HOPEDALE SOILS (HP)
Location and Extent : Hopedale soils occupy scattered locations on the lowlands of the map area, mainly i n
the eastern half. The largest areas are in Glen and Hatzic Valleys and east of Vedder Canal . There are about 250
ha of pure map units and 530 ha of soil complexes dominated by Hopedale soils . Most complexes are wit h
McElvee, Isar and Sardis soils .
Topography and Elevation : Gently undulating to undulating or gently sloping with slope gradient s
between 2 and 5 percent is the usual topography of Hopedale soils . They occupy slightly depressiona l
locations when associated with better drained soils and lie between 4 and 10 m above sea level .
Parent Material and Texture : Hopedale soils have developed from medium-textured, stone-free, loca l
stream deposits and some fan deposits . The deposits are between 20 and 50 cm thick and lie over coarse -
textured sediments . Surface and subsurface textures are mostly silt loam, sometimes varying to loam, whil e
subsoils are sand or loamy sand, occasionally gravelly and containing loamy lenses .
Soil Moisture Characteristics : Hopedale soils are poorly drained . They are moderately to rapidly perviou s
and have moderate water holding capacity and slow surface runoff. High watertables are usual for most of the
winter and after heavy rains ; seepage from adjacent streams is common also .
General Soil Description : Hopedale soils have a grayish-brown, friable, silty, cultivated surface laye r
between 15 and 20 cm thick . This is underlain by about 25 cm of olive-gray or grayish-brown, friable to firm ,
massive to medium blocky, silty material containing common to many, yellowish-red to strong brown mottles .
This is either abruptly underlain or grades to gray or dark gray sandy deposits that are variably mottled an d
sometimes contain thin, silty lenses . Soil reaction is usually medium acid throughout (1 :1 H 2 O) . Soil classification
is mainly Rego Gleysol; some Orthic Gleysol also occurs where the subsurface layer is moderatel y
structured .
Commonly Associated Soils : McElvee, Sardis, Isar and Bates soils are usually closely associated wit h
Hopedale soils . Sardis and Isar soils differ from Hopedale soils by being better drained and having sandy an d
gravelly textures throughout . McElvee soils are similar to Hopedale except that the silty capping over sand i s
more than 50 cm thick . Bates soils differ by being imperfectly drained and also have 50 cm or more of silty
material over sand .
Vegetation : Most areas of Hopedale soils are cleared and cultivated . Uncleared areas support, amon g
others, black cottonwood, western red cedar, red alder, willow, vine and bigleaf maple, salmonberry, thimblebe -
rry, sedges, grass . Rooting is mainly limited to the upper 75 cm by high watertables .
General Land Use Comments : (1) Hopedale soils are used mainly for hay, pasture and some corn, pea s
and other field crops . Poor drainage during the winter and early part of the growing season and somewha t
droughty conditions during the latter part of the summer are the main agricultural limitations . Watertable contro l
and irrigation make these soils capable of producing a wide range of crops . (2) High watertables and moderat e
bearing capacities limit Hopedale soils for urban and related uses . Excavations such as basements wil l
probably contain water during parts of the year and efficient functioning of septic tanks is impaired by the hig h
watertables . Potential groundwater contamination may occur if numerous septic tanks are installed, due t o
incomplete filtration by the coarse textured subsoils . (3) Hopedale soils are well suited for black cottonwoo d
and potential annual wood production by this species is estimated to be between 12 and 15 m3/ha .
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