Soils of the - Agriculture and Agri-Food Canada

MARBLE HILL SOIL S
Location and Extent : Marble Hill soils occupy substantial upland areas throughout the eastern part of th e
map area . The largest areas are in the vicinities of Abbotsford and Mission . About 1610 ha of pure map units an d
1830 ha of soil complexes dominated by Marble Hill soils are mapped . The complexes are usually wit h
Abbotsford, Ryder, Calkins and Laxton soils .
Topography and Elevation : Topographically, Marble Hill soils vary from very gently sloping or gentl y
undulating to hilly with slopes between 2 and 40 percent . Usually, however, they are undulating to gently rollin g
with slopes from 4 to 15 percent . Elevations mostly lie between 30 and 100 m above sea level but some areas
rise to 200 m .
Parent Material and Texture : Marble Hill soils have developed from medium-textured, stone-free, eolia n
deposits, greater than 50 cm thick, which overlie gravelly glaciofluvial deposits . The eolian material is mostly sil t
loam, sometimes varying to loam or fine sandy loam, while the underlying glaciofluvial deposits are either sand y
gravel or gravelly sand .
Soil Moisture Characteristics : Marble Hill soils are well drained . They are moderately pervious and have
moderate to high water holding capacity and slow surface runoff .
General Soil Description : In uncleared areas Marble Hill soils have up to 5 cm of raw to well-decomposed ,
organic forest litter on the mineral soil surface . This is underlain by 50 cm or more of friable, weakly structured ,
silty material which ranges from dark reddish brown in the upper part to dark yellowish brown at depth an d
contains variable amounts of rounded, hard, reddish concretions . The subsoil below the silty eolian material i s
loose, single-grained gravel or gravelly sand, sometimes containing weakly cemented patches . Soil reaction i s
strongly acid throughout . Soil classification is Orthic Humo-Ferric Podzol.
Commonly Associated Soils : Abbotsford, Ryder, Lonzo Creek, Calkins and Laxton soils often occur i n
close association with Marble Hill soils . The surfaces of Abbotsford and Laxton soils are similar to that of Marbl e
Hill soils . In Abbotsford soils however, the gravelly underlay occurs between 20 and 50 cm of the surface while ,
in Laxton soils, the underlay is sandy . Ryder and Lonzo Creek soils also have surfaces similar to Marble Hil l
soils, however their subsoil is compact glacial till rather than gravelly glaciofluvial deposits . The glacial till i n
Ryder soils occurs at depths greater than 50 cm while, in Lonzo Creek soils it is encountered between 20 and 5 0
cm of the surface . Calkins soils differ from Marble Hill soils by being poorly drained and having a black surface .
Vegetation : Substantial areas of Marble Hill soils are cleared and cultivated . Uncleared areas support a
variable forest which includes coast Douglas-fir, western hemlock, red alder, vine and bigleaf maple an d
western red cedar. The undergrowth includes salai, bracken, Pacific dogwood, trailing blackberry and moss .
Rooting depth is unrestricted .
General Land Use Comments : (1) Marble Hill soils are suited for most agricultural crops althoug h
adverse topography is limiting in some areas . They tend to become droughty during dry growing seasons an d
irrigation is required to maintain good productivity . (2) Marble Hill soils are generally well suited for urban an d
related uses . They are well-drained and the subsoil gravels provide good foundation conditions . Potentially,
groundwater contamination can occur if septic tanks are intensively installed, due to incomplete filtration by th e
coarse-textured subsoil . Areas of Marble Hill soils are potential aggregate sources . (3) Forest productivity i s
moderate to high ; the main limitation seems to be soil moisture deficiencies during the latter parts of mos t
growing seasons . Data from a limited number of plots indicates potential annual wood production by coas t
Douglas-fir is about 7 .5 to 9 m 3/ha .
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