Soils of the - Agriculture and Agri-Food Canada

LONZO CREEK SOILS ,(LZ)
Location and Extent : Lonzo Creek soils occupy substantial upland areas in the eastern part of the ma p
area . About 510 ha of pure map units and 9420 ha of soil complexes dominated by Lonzo Creek soils ar e
mapped . The complexes are mostly with Ryder, Cannell, Poignant and Abbotsford soils .
Topography and Elevation : Lonzo Creek soils are mostly gently to strongly rolling although undulating o r
hilly areas also occur . Slopes vary from 3 to 50 percent but most commonly are between 8 and 25 percent .
Elevations range from 20 to 300 m above sea level .
Parent Material and Texture : Lonzo Creek soils have developed from shallow (20 to 50 cm thick), medium -
textured, stone-free eolian deposits that overlie moderately coarse textured, compact glacial till . The texture o f
the eolian material is mostly silt loam, occasionally varying to loam or fine sandy loam while the glacial till i s
gravelly sandy loam or loam .
Soil Moisture Characteristics : Lonzo Creek soils are well to moderately well drained . They are moderatel y
pervious in the silty eolian capping ; this changes to moderately or slowly pervious in the underlying glacial till .
They have moderate water holding capacity and slow to moderate surface runoff . Very temporary perche d
watertables develop above the glacial till during periods of heavy rain and lateral seepage occurs during these
times also .
General Soil Description : Lonzo Creek soils, in uncleared areas, generally have up to 5 cm of variabl y
decomposed ; organic forest litter on the soil surface . The organic material is underlain by between 20 and 5 0
cm of reddish-brown to yellowish-brown, friable, weakly structured, silty material containing variable amounts o f
fine, rounded concretions . Underlying the silty material, often abruptly, is pale brown or grayish-brown, massiv e
to weakly stratified, compact, moderately stony, loamy glacial till . Soil reaction varies from medium to strongl y
acid throughout (1 :1 H2 O). Soil classification is Orthic Humo-Ferric Podzol.
Commonly Associated Soils : Ryder, Abbotsford, Marble Hill, Poignant and Cannell soils often occu r
closely associated with Lonzo Creek soils, either in soil complexes or occupying adjacent map polygons .
Ryder soils are similar to Lonzo Creek soils except that the depth of the silty eolian capping is greater than 5 0
cm . Abbotsford and Marble Hill soils differ from Lonzo Creek soils by being underlain by gravelly glacio-fluvia l
materials rather than glacial till . Poignant soils differ by being composed of mixed silty eolian material and ston y
colluvium while Cannell soils differ by being underlain by bedrock within 100 cm of the surface .
Vegetation : Substantial areas of Lonzo Creek soils are currently cleared and cultivated . The uncleared areas
support second-growth forest, mainly consisting of coast Douglas-fir, western hemlock, red alder, bigleaf an d
vine maple and some western red cedar. Rooting is mostly restricted to the upper 50 cm by the compact ,
subsoil glacial till . Root concentrations (root mat) often occur immediately above the glacial till .
General Land Use Comments : (1) Lonzo Creek soils are suited for most agricultural crops althoug h
adverse topography is limiting in some areas . The soils tend to be droughty and irrigation is required in mos t
years to ensure good production . (2) Lonzo Creek soils are moderately suited for urban and related uses . Th e
underlying glacial till provides firm foundations although its relatively low permeability limits septic tank effluen t
disposal . Adverse topography is limiting in some areas and surface erosion is likely to occur in areas of bar e
soils . (3) Forest production is moderately high, limited mainly by droughty conditions during the latter part of th e
growing season . Data from a limited number of plots indicates that the potential annual wood production b y
coast Douglas-fir is between 7 .5 and 9 m3/ha.
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