1868.] DAWSON — RESTORATION OF FORESTS. 411 



circumstances may occur which will prevent this restoration of 

 the primeval forest. 



In accounting for the presence of the seeds necessary for the 

 production of the second growth, we may refer to the same 

 causes which supply the seeds of the smaller plants appearing 

 immediately after the fire. The seeds of many forest trees, 

 especially the poplar, the birch, and the firs and spruces, are 

 furnished with ample means for their conveyance through the air. 

 The cottony pappus of the poplar seems especially to adapt it for 

 this purpose. The seeds of the wild cherry, another species of 

 frequent occurrence in woods of the second growth, are dispersed 

 by birds, which are fond of the fruit ; the same remark applies to 

 some other fruit-bearing species of less frequent occurrence. 

 When the seeds that are dispersed in these ways fall in the 

 growing woods, they cannot vegetate ; but when they are deposit- 

 ed on the comparatively bare surface of a barren, they readily 

 grow ; and if the soil is suited to them, the young plants increase 

 in size with great rapidity. 



It is possible, however, that the seeds of the trees of the 

 second growth may be already in the soil. It has been already 

 stated, that deeply-buried tubers sometimes escape the effects of 

 fire ; and, in the same manner, seeds embedded in the vegetable 

 mould, or buried in cradle hills, may retain their vitality, and, 

 being supplied by the ashes which cover the ground with alkaline 

 solutions well fitted to promote their vegetation, may spring up 

 before a supply of seed could be furnished from any extraneous 

 source. It is even probable that many of the old forests may 

 already have passed through a rotation similar to that above 

 detailed, and that the seeds deposited by former preparatory 

 growths may retain their vitality, and be called into life by the 

 favourable conditions existing after a fire. 



If, as already suggested, forest fires, in the uncultivated state 

 of the country, be a provision for removing old and decaying 

 forests, then such changes as those above detailed must have an 

 important use in the economy of nature, since by their means 

 different portions of the country would succeed each other in 

 assuming the state of ' barrens,' producing abundance of herbs 

 and wild fruits suitable for the sustenance of animals which could 

 not subsist in the old woods; and these gradually becoming 

 wooded, would keep up a succession of young and vigorous 

 forests. 



