Grass 



rushes near sheets of fresh water, and other grasses 

 also occur in wet placed. Then, on the other hand, 

 the bent-grass, Psamma, grows in very dry ground, and 

 a sand-dune overgrown with it is not unUke a steppe. 

 All these are natural grass-lands. 



But in the United States the prairie, which is a 

 typical grass-land, is bounded on the east or Atlantic 

 side by a country which is or used to be a thick and 

 well-grown forest. On the Rocky Mountains or western 

 side, the prairie becomes gradually more and more 

 steppe-like and arid until real desert begins. It is 

 just the same with the pampas of the Argentine. In 

 the west at least it shades off into a desert, whilst on 

 the east there are or used to be the forests and woods 

 of the Rio de la Plata. 



It seems very probable that a considerable proportion 

 of the eastern prairie, and very likely of the Argentine 

 pampas as well, was once woodland or forest ; at any 

 rate many American botanists seem to think so. The 

 Indians used to set fire to the woods in order to 

 obtain land for cultivation. Prairie fires, happening in 

 a late and dry summer when everything is scorched 

 and inflammable, would inevitably prevent the growth 

 of woodlands. If this is so, it is only a natural grass- 

 land in the sense that natural man, not the intelligent 

 and civilised variety, has produced it. 



The author has himself seen the effect of grass fires 

 upon the African plateaux in Uganda. It is not a 

 very alarming or dangerous spectacle, for it is just an 

 insignificant line of blazing grass which may be some- 

 times checked by a hard-trodden native path, and which 

 one can step over without any danger. 



In that district, each river is bordered by a fringe of 

 woodland ; the fire does not usually destroy the foliage 

 but only singes the outlying branches of the outside 



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