Soils of the - Agriculture and Agri-Food Canada

HOLLYBURN SOILS (HB)
Location and Extent : Hollyburn soils are relatively common at the higher elevations of the mountainous ,
northern part of the map area . About 620 ha of pure map units and 8760 ha of soil complexes dominated by
Hollyburn soils are mapped . The complexes are mainly with Dennett, Sayres and Grouse soils and Roc k
Outcrop land type .
Topography and Elevation : The topography of Hollyburn soils is mostly moderately rolling to hilly wit h
slope gradients between 10 and 50 percent . Elevations are generally 1000 m or more above sea level .
Parent Material and Texture : Hollyburn soils have developed from moderately coarse to coarse-textured ,
stony deposits of colluvium, glacial till or mixed colluvium and till which are less than 1 m deep and overli e
bedrock . There is usually 5 to 10 cm of variably decomposed organic material on the mineral soil surface . Th e
textures of the mineral soil are mainly gravelly sandy loam or sandy loam, with some variation to gravelly loam y
sand .
Soil Moisture Characteristics : Hollyburn soils are well to moderately well drained . They are rapidl y
pervious and have low water holding capacity and moderate to slow surface runoff. Lateral seepage along the
underlying bedrock surface is usual during heavy rains and snowmelt, especially where the bedrock is relativel y
massive .
General Soil Description : Hollyburn soils generally have 5 to 10 cm of variably decomposed organi c
material on the mineral soil surface . This is underlain by up to 5 cm of discontinuous, leached, gray, friable ,
sandy material which, in turn, is underlain by about 30 cm of sandy material which is weakly structured, friabl e
and ranges in colour from reddish-brown or yellowish-brown near the top to brown or dark brown near th e
bottom . This zone either directly overlies bedrock or is separated from the bedrock by a sandy zone that is olive -
gray to gray, massive and friable . Soil reaction grades from extremely acid in the surface to strongly acid abov e
the underlying bedrock . Soil classification is mainly Orthic Humo-Ferric Podzol:lithic phase with some incl u
sions of Orthic Ferro-Humic Podzol :lithic phase and Sombric Humo-Ferric Podzol :lithic phase where organi c
matter enrichment of the surface and subsurface mineral soil layers is higher than usual .
Commonly Associated Soils : Grouse, Dennett and Sayres soils and Rock Outcrop land type generally ar e
closely associated with Hollyburn soils . Grouse soils differ from Hollyburn soils by being imperfectly draine d
and having a well defined, organic matter enriched, dark coloured, surface mineral soil layer . Dennett soil s
differ by consisting of 10 cm or more of organic material over bedrock while Sayres soils differ by having well -
developed organic matter accumulation layers in the subsurface . The Rock Outcrop land type differs b y
consisting either of less than 10 cm of soil material (organic or mineral) over bedrock or has rock exposed at th e
land surface .
Vegetation : Hollyburn soils occur in the subalpine parkland and in lower alpine areas . The vegetation i s
typical of this zone and includes, among others, scattered, usually stunted, yellow cedar, mountain hemloc k
and Pacific silver fir as well as various heathers, blueberries, sedges and mosses . Rooting is restricted to th e
depth of soil above bedrock (less than 1 m) .
General Land Use Comments : (1) High elevations, harsh climate, adverse topography, and shallownes s
to bedrock preclude agricultural uses of Hollyburn soils . Similar limitations also prevent urban and related uses .
(2) Forest growth is poor, mainly due to the inclement climate . (3) Spectacular scenery makes hiking and similar
recreational uses attractive . Trails and other construction should be carefully located to prevent damage to th e
relatively fragile, slow to recover plant communities .
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