The Tree Planting Problem, etc. 



127 



distance of about 5U0 miles, the lack oi 

 tree growth never fails to be remarked. 

 It is a great stretch to be practically 

 without trees and its breadth is in pro- 

 portion, for it extends from the bound- 

 ary line at least two hundred miles 

 north, and in all this vast area practic- 

 ally the only indigenous trees are a few 

 scattered specimens dotted along the 

 river bottoms, with the exception of the 

 forest on the Cypress Hills (a strip of 

 about forty miles long by ten or fifteen 

 broad). The rest of this immense area 

 is practically treeless, except where some 

 enterprizing farmer has made a begin- 

 ning towards doing his share of furnish- 

 ing a much-needed complement to the 

 prairie landscape. 



Causes Contributing to Tree- 

 lessness. 

 The causes contributing to this tree- 

 lessness have been much discussed. 

 Undoubtedly the cheif cause has been 

 fire; even before the coming of the 

 white man the prairie was often fired 

 by the Indians, usually either to cir- 

 cumvent an enemy or to provide grass 

 for the buffalo during the following 

 season. The very richness of the prairie 

 soil, which caused such a luxuriant 

 growth of grass that the young trees 

 were eventually smothered, and the 

 comparatively low rainfall of southern 

 Alberta and southern Saskatchewan, 

 preventing the germination of seeds, 

 also contributed largely to this result. 



The Chinooks. 

 The chinook winds of Southern 

 Alberta and the western portions of 

 South Saskatchewan were also powerful 

 factors in checking the natural spread 

 of tree growth, but their most important 

 effects were exerted indirectly rather 

 than in the way many of the old timers 

 thought. The chinooks are warm winds 

 which come over the mountains from 

 British Columbia, and in summer, after 

 a day or two's vigorous "chinooking", 

 the grass gets crisp and brown and the 

 water holes dry up very rapidly. In 

 winter the chinook makes the snow 

 disappear as if by magic, and it looks 

 as if a slice of early spring or fall had 

 suddenly been sandwiched into the 

 heart of winter. Both these conditions 

 are peculiarly favorable to the progress 

 of a prairie fire, and thus is brought 

 about the significant fact that in the 



district mentioned it was possible for a 

 prairie fire to sweep over the entire 

 country any time of the year except 

 about two months in the very vigor of 

 the growing season. Very small indeed 

 were the chances of any tree seedlings 

 surviving many seasons under conditions 

 like these. 



At one time it was thought that the 

 warmth of the chinooks encouraged the 

 flow of sap in winter and that a sudden 

 frost immediately following killed the 

 trees, but this is a theory that has not 

 much to support it. There may have 

 been cases where this has occurred, but 

 it has not been general and probably 

 confined only to introduced trees. If 

 this thawing and freezing have had any 

 large share in bringing about the tree- 

 lessness of the prairie, why do we find 

 such fine specimens of poplar in the 

 valleys of the Old Man, the Bow and 

 other rivers of Alberta? and why do 

 we find usually a fringe of pine trees, 

 commonly Lodgepole Pine or Western 

 White Pine, along the crests of the hills 

 north of Pincher Creek? These trees 

 stand right in the teeth of the chinooks, 

 and if there were much in this theory of 

 thawing and freezing surely that is 

 where it would be most felt. But no' 

 there they stand, some of the poplars 

 50 or 60 feet high, and doubtless close to 

 100 years old, proof positive that on 

 them at least the chinooks have had no 

 evil effects. The surrounding country 

 is bare because of repeatedly recurring 

 fires from which these trees were pro- 

 tected by the snow drifts along the edge 

 of the river valleys. A visit to the 

 fringes of pines will soon convince the 

 observer that they also were saved by 

 their surroundings, for they are growing 

 either in rocky land where there was no 

 grass to carry over the fires, or among 

 ground cedar (or, rather, dwarf juniper) 

 which would not burn, and so kept the 

 fires at a distance. 



The Settlers. 

 The first settlers were cattle ranchers 

 and such a country suited them well. 

 There was abundance of grass and water, 

 and although some of them may have 

 wished for a little more tree shelter for 

 their stock very few took the trouble to 

 find out if trees would grow or not. Those 

 who did usually found their attempts 

 ended in failure and till within a few 

 years ago the general opinion was that 



