7 
The account of the vegetation will be preceded by general descriptions 
of the topography, soils, and geological history of the region. Detailed 
descriptions of these features in local areas, however, will be relegated to 
discussions of plant distribution. 
The investigation would be incomplete without acknowledgment of 
the many kindnesses and the assistance rendered the field parties. It would 
be impossible to enumerate all those who have helped to forward the work, 
but the writer wishes to express his thanks especially to Mr. J. A. 
MacDougal, District Agent at Fort Smith, whose organization in the 
park supplied the necessary transportation, and to the officers of the 
Hudson’s Bay Company, who have been most helpful in outfitting. Many 
persons have assisted in the systematic work on the flora, and will be 
mentioned as the occasion arises. Especial thanks are due to the Carnegie 
Museum of Pittsburgh, Pennsylvania, and to the Gray Herbarium of 
Harvard University, for the use of their collections and libraries in working 
up the material. The present report has been prepared during the writer’s 
tenure of a National Research Council Fellowship in the Biological 
Sciences. 
TOPOGRAPHY AND SOILS 
The highest land in Wood Buffalo park is in Caribou Mountain pla- 
teau, only a part of which lies inside the western boundary. This plateau 
reaches an elevation of about 3,500 feet above sea-level, and appears to be 
a part of an ancient, much dissected upland. Very little of it has ever been 
described, but judging from a few scattered references and the writer's 
observations, it is rather flat-topped, with margins deeply dissected by rapid 
streams. The eastern slope is of morainic materials and is gradual up to 
about 1,400 feet, where a noticeable steepening occurs, and there are what 
may be classed as terminal morainic deposits, modified to form what 
appear to be shore terraces. At higher levels there are long, gradual slopes 
which have no rolling character. 
In a few places, at an altitude of about 2,000 feet, the writer has found 
bluish clay soils, part of which are known to have weathered, in situ, from 
shales that outcrop at this elevation. A discussion of these and their 
distribution will be found in a discussion of the forest types that appear 
on the upland. 
The only other elevation of note is the northern margin of Birch moun- 
tain, which comes into the park along the southern boundary. This high- 
land rises about 2,300 feet above the sea (21) . Stretching north and east from 
these uplands is a gently rolling plain known as the Alberta plateau (22) . A 
considerable part of its northern margin lies within the park, and is marked 
by a well-defined escarpment reaching from a region southwest of Fort 
Smith, northwestward and northward across Little Buffalo river, and 
finally westward toward Buffalo lake. Its position is marked by falls and 
rapids on the upper Little Buffalo and on the western tributaries of this 
stream, such as Clewi, Sass, Bear, and Nyarling rivers. The Little Buffalo 
has cut a gorge about 6 miles long below the falls. In the area southwest of 
Fort Smith it is known as the Salt Mountain escarpment, and forms the 
southwestern border of the plain of Salt river. The southward extension 
of the escarpment has not been clearly defined. 
