SOIL SURVEY

-26-At slightly higher positions and where seepage is not present the occurranc eof free water does not control the profile development . However, temporary floodingon these sites causes frequent horizon disruption, through scouring and/or depositionof fluvial materials, resulting in soils classified within the Regosolic order (see descriptionof KI 1) . Time, or rather the lack of it, is the dominant soil-forming factor i nthis group of soils . Soils developed on steep colluvial slopes also occur in the tw ovegetation zones . In this case soil creep and downslope movement result in continuousprofile disruption . Here again time is the dominant soil-forming factor (see descriptio nof BG 3) .Soils developed on well drained, gently sloping glaciofluvial and fluvia lmaterials are closely related to soils on the adjacent fluvial landforms even thoug hthey reflect the soil-forming factors of climate and vegetation . This similarity i nmaterials and landforms led to the grouping of these Brunisolic soils with the adjacen tRegosolic and Gleysolic soils for the purposes of the Generalized Soils Map . Thes eBrunisolic soils typically have a thin leaf litter, 1 to 2 cm of Ae horizon and 15 t o25 cm of yellowish red Bm horizon with lime occurring below (see description of TA 1) .Soils of the Subalpine ZoneWithin this vegetation zone (elevations of approximately 1,550 to 2,000 ma .s .l .) the soil-forming factors of climate and vegetation control the differentialgenetic development except where the steepness of the slopes results in sufficien tdownslope movement to interrupt horizon development .Where the climate and vegetation express themselves fully, soils of thePodzolic order are the result . When unusually calcareous or finer textured paren tmaterials slow the rate of profile development soils of the Brunisolic order often occu rintimately associated with the Podzolic soils .The influence of the soil-forming factor of parent material under fairly constan tclimate and vegetation factors is shown by the contrasting soils in the Lake O'Haraarea and in the upper Yoho valley . The parent materials in the Lake O'Hara area ar ecoarse textured till materials which are non to slightly calcareous . In these soils