TEEES AND FUTUKE FOKESTS OF THE PLAINS. 485 



hundredth meridian. The elm and ash are of similar, perhaps 

 greater range. Hackberry has been observed west of one 

 hundred and first meridian. Cottonwood, elder, red cedar, 

 plum, and willow are persistent to the base of the mountains. 

 The extensive pine forest on the ' great divide ' south of Den- 

 ver, although stretching seventy to eighty miles east from the 

 mountains, is not taken into view as belonging to the plains 

 proper. Its existence, however, suggests the use of its seeds in 

 artificial plantations in that region. The fossil wood imbedded 

 in the cretaceous strata in many parts of the plains is left out 

 of consideration, as belonging to a previous, though recent, geo- 

 logical age; but the single specimens of trees found growing at 

 wide intervals are silent witnesses to the possibility of extended 

 forest growth. 



" Were it possible to break up the surface to a depth of two 

 feet, from the ninty-seventh meridian to the mountains, and 

 from the thirty-fifth to the forty-fifth parallel, we should have 

 in a single season a growth of taller herbage over the entire 

 area, less reflection of the sun's heat, more humidity in the 

 atmosphere, more constancy in springs, pools, and streams, 

 more frequent showers, fewer violent storms, and less caprice 

 and fury in the winds. A single year would witness a changed 

 vegetation and a new climate. In three years (fires kept out) 

 there would be young trees in numerous places, and in twenty 

 years there would be fair young forests. The description of 

 the ' broad, grassy plains/ given in the foregoing pages, attests 

 their capacity to sustain animal life. For cattle, sheep, horses, 

 and mules, they are a natural pasture in summer, with (in 

 many parts) hay cured standing for winter. The famed Pam- 

 pas, with their great extremes of wet and drought, can not 

 bear comparison with our western plains. For grazing pur- 



