Soils of the - Agriculture and Agri-Food Canada

ANNIS SOILS (AN)
Location and Extent : Annis soils occupy small, scattered areas throughout the lowlands, mainly in Mission ,
Langley, Matsqui, Sumas and Pitt Meadows Municipalities . There are about 650 ha of pure map units and a
further 540 ha of complexes dominated by Annis soils . The complexes are mostly with Richmond, Hjorth ,
Hazelwood and Banford soils .
Topography and Elevation : Annis soils are slightly depressional to gently undulating with slopes up to 2
percent . They usually occupy slightly lower landscape positions in relation to adjacent soil s: All Annis soil area s
occur at elevations less than 10 m above sea level .
Parent Material and Texture : Annis soils have developed from shallow organic accumulations (between 1 5
and 40 cm thick) which overlie moderately fine to fine-textured Fraser River floodplain deposits and som e
lacustrine and deltaic deposits . Surfaces consist of 15 to 40 cm of usually well-decomposed organic material .
Subsurface and subsoil textures are silty clay loam or silty clay . Below about 1 m depth these grade to mediu m
or fine sand which, in the deltaic deposits, may be saline .
Soil Moisture Characteristics : Annis soils are poorly to very poorly drained . They are slowly pervious an d
have high waterholding capacity and slow surface runoff . The watertable is at or near the surface for most of th e
winter and after other heavy rains as well as during the freshet period of the Fraser River . It however, retreats to a
depth of a metre or more during dry summers . The soils often act as catchments for the runoff from higher ,
adjacent land . Artificial drainage has been installed in some areas .
General Soil Description : The surface of Annis soils consists of 15 to 40 cm of dusky red to dark brown ,
variably decomposed organic material, sometimes stratified . This is underlain by 50 cm or more of massive ,
gray to dark gray, silty clay loam or silty clay which contains few to common, brown and reddish-brown mottles .
This zone then either grades gradually or changes abruptly to medium or fine sand below about 1 m . For most of
the year the sand is saturated with water. Soil reaction is extremely acid in the organic surface and grades t o
medium acid in the subsoil . Soil classification is Rego Gleysol:peaty phase .
Commonly Associated Soils : Banford, Hallert, Gibson, Hjorth and Hazelwood soils are all commonl y
associated with Annis soils . Banford and Gibson soils differ from Annis soils by respectively consisting of 40 t o
160 cm of well-decomposed (humic) organic material and 40 to 160 cm of partially decomposed (mesic )
organic material . The surface of Hjorth and Hazelwood soils is mineral in texture (silty) while Hallert soils ar e
composed of alternating layers of organic and silty material .
Vegetation : All areas are cleared and used mainly for pasture and forage . Rooting depth is usually restricte d
to about 60 cm by dense, clayey subsoil textures and high watertables .
General Land Use Comments : (1) Poor drainage and heavy subsoil textures limit the utilization of Anni s
soils for agriculture . Artificial drainage, where not already installed, will widen the range of suitable crops fro m
the usual pasture and forage species to include most annual field crops . Improved drainage will also allo w
earlier cultivation in the spring . (2) High watertables and variable bearing capacities make road and buildin g
construction difficult. Septic tank effluent disposal fields function poorly while basements and other excavations
are impractical due to high watertables .
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