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ASPEN POPLAR (Populus tremvlmdes) may be called the characteristic tree 

 of the plains. Wherever there is dry soil, not too sandy, outside of allu- 

 vium, there is aspen. I have passed repeatedly from aspen " bluffs " on 

 the prairies, not twenty feet high, and with the trees not thicker than a 

 walking stick, to continuous forests of stately trees, with their white 

 trunks towering to the skies. Each time I have noticed that the forest 

 was only kept in check by the annual fires. Until the willow and aspen 

 roots had lost their vitality, they persisted in sending up crop after crop 

 of stems ever increasing in number, until death by exhaustion took place 

 and permanent prairie was formed. It has been frequently stated that 

 aspen seeds remain in the soil, but this is not so. The reason it reclothes 

 the ground so many times after being swept off by fire, is the fact that it 

 throws up shoots from every root after a fire has killed the stem. It pos- 

 sesses this quality, in common with all members of the Willow family, 

 which it is well known grow indiscriminately from either roots or 

 planted stems, and very seldom from seeds. This provision ueems neces- 

 sary to this order (Salicacese), as in all cases the flowers are dioecious and 

 two trees in close proximity are necessary to perfect the seed. Two 

 notable instances of this are found in the White Poplar (Popvlus alba) 

 and Lombardy Poplar, which produce no fertile seed in the absence of the 

 staminate tree. 



THE COTTONWOOD (Popvlus monilifera) is found in the deep river val- 

 leys of the " Great Plains," and occasionally amongst sand hills, but in 

 no place is it so abundant as to deserve particular notice for its economic 

 importance, though, when found, it is usually of large size. It is the last 

 remnant of the former forests of the south. Its thick coarse bark, like 

 that of the oak, preserves it from the repeated assaults of the annual fires, 

 and enables it to escape when thin-barked trees succumb. 



THE OAK (Quercus macrocarpa var.) grows to a large size in many parts 

 of Manitoba, but it is unknown to the west of it. In that part of Mani- 

 toba, south of the Assiniboine and west of the Pembina Mountain, there 

 are numerous groves of fine trees and much of the timber is valuable for 

 a variety of purposes. It is also common on the White Mud River, and 

 is frequently seen in groves along Lake Manitoba. 



ELM ( Ulmus Americana) is never found outside of river bottoms, except 

 along Lakes Manitoba and Winnipegoosis. It grows to a very large size 

 in the valleys of the Red and Assiniboine Rivers, and often forms groves 

 of large extent In lat. 53, along the Red Deer River, which empties 

 into the northern end of Lake Winnipegoosis, are large groves of very 

 fine elms often four feet in diameter. It is found in some abundance on 

 Carrot River and the Saskatchewan, but is confined to low alluvial flats. 



ASH (Fraodnus pubescens) grows in the valleys of the Assiniboine and 

 Red Rivers, often forming groves, but the timber, though frequently tall, 

 never attains a large size. It is scattered throughout all the prairie 

 country, and is found as a small tree in the river valleys and along the 

 broken face of the Coteau and Cypress Hills. It is of no value for tim- 

 ber, but makes excellent firewood even when green. 



