Soils of the - Agriculture and Agri-Food Canada

STAVE SOILS
Location and Extent : Stave soils occur mostly on the uplands north of the Fraser River and east fro m
Alouette Lake . About 660 ha of pure map units and 480 ha of soil complexes dominated by Stave soils ar e
mapped . The complexes are mostly with Keystone, Roach and Buntzen soils .
Topography and Elevation : The topography of Stave soils is variable, ranging from gently sloping o r
undulating to strongly sloping or moderately rolling . Slopes are usually between 2 and 15 percent but alon g
incised streams, the gradients rise to 60 percent . Elevations mainly lie between 100 and 200 m above sea level .
Parent Material and Texture : Stave soils have developed from moderately coarse to coarse-texture d
(sandy) littoral, glaciofluvial or sometimes, lacustrine deposits at least 1 m thick which are underlain usually b y
glacial till or occasionally, glaciomarine deposits . Shallow (less than 50 cm thick) deposits of silty aeolian
material usually are mixed into the upper part of the coarser material . Surface textures range from sandy loam t o
loam . The subsurface varies from loamy sand to coarse sand while the subsoils are mostly coarse sand o r
gravelly sand, often containing numerous stones, cobbles and boulders . Moderate numbers of stones are
sometimes present in the surface . The glacial till which occurs at depth is compact, dense, gravelly sand y
loam .
Soil Moisture Characteristics : Stave soils are well to moderately well drained . They are rapidly perviou s
although some hinderance to moisture movement occurs in the lower subsoil due to moderate, discontinuou s
cementation in some locations . Permeability of the underlying till or glaciomarine material is low, leading t o
seepage along the surface of this zone . Areas of Stave soils along the margin of Stave Lake may have
watertables in the subsoil depending on the height of the water level in the lake . The soils have slow surface
runoff and low to moderate water holding capacity.
General Soil Description : Stave soils usually have 10 cm or less of variably decomposed, organic fores t
litter on the soil surface . This is underlain by 2 to 5 cm of gray to reddish-gray, friable, strongly leached, sandy to
loamy material . The leached layer is abruptly underlain by about 20 cm of dark reddish brown or reddish-brown ,
friable, weakly structured, loamy soil often containing moderate amounts of stones and common, hard, reddis h
concretions . This zone then grades to about 40 cm of sandy material which is friable, weakly structured an d
varies from reddish-brown in the upper part to yellowish-brown in the lower part and may contain moderat e
amounts of stones . Under this is about 40 cm of yellowish-brown to olive, sandy material containing variabl e
amounts of stones and boulders as well as discontinuous, moderately cemented patches and a few mottles . A
loose to very firm (due to cemented patches) zone is then encountered which consists of gravelly sand tha t
contains common, reddish or yellowish mottles and often excessive amounts of stones and boulders . Seepage
is present during parts of the year . At depths of at least 1 m, dense, compact glacial till or glaciomarine deposit s
occur. Soil reactions grade from extremely acid in the surface to strongly acid in the subsoil . Soil classification i s
Orthic Humo-Ferric Podzol.
Commonly Associated Soils : Keystone, Roach and Buntzen soils are often closely associated with Stav e
soils . Buntzen soils differ from Stave soils by being developed from glacial till and contain strongly cemente d
subsoil layers . Keystone and Roach soils are both gravelly in texture and have strong cementation in th e
subsurface and/or subsoil . Stave soils are somewhat similar to Sunshine soils . Sunshine soils however hav e
coarser textured surfaces and are stone-free .
Vegetation : Most areas of Stave soils have been logged and now support second-growth western hemlock ,
western red cedar and coast Douglas-fir as well as red alder and maple . Rooting depth is essentiall y
unrestricted to at least 100 cm, then becomes variably restricted by the discontinuous cementation an d
underlying dense geologic materials .
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