82 ITS WONDERFUL FERTILITY. 



of three tons of nitrogen, and as a heavy crop of wheat with 

 its straw contains about fifty-two pounds of nitrogen, there is 

 thus a natural store of ammonia in this soil sufficient for more 

 than a -hundred wheat crops. In Dr. Voelcker's words, "it is 

 this large amount of nitrogen, and the beautiful state of divi- 

 sion, that impart a peculiar character to the soils, and dis- 

 tinguish them so favourably. They are soils upon which I 

 imagine flax could be grown in perfection, supposing the cli- 

 mate to be otherwise favourable. / have never before analysed 

 soils which contained so much nitrogen, nor do I find any record of 

 soils richer in nitrogen than these" 



CROPS. 



Though these soils are so rich in nitrogen, they seem to be 

 too loose for wheat, which is undoubtedly a precarious crop 

 upon them. The open prairie country is so wind-swept in 

 winter that snow seldom lies long to any depth, and the young 

 wheat is thus left unprotected to the frost. Should it escape 

 that, it is liable to be thrown out by the rapid changes of 

 weather in spring, and if it is fortunate enough to escape 

 both, it is sometimes destroyed, as it was last year, by its 

 enormously rapid growth in forcing summer weather, growing 

 as it does almost on a muck-heap. In such a season as the 

 last, the prairie wheat crops of Illinois were injured precisely 

 in the same manner as our own in this country sometimes suf- 

 fer from a too heavy dose of guano, in a warm moist summer. 

 The growth is too rapid, the vesicles of the stem burst, and 

 the ear does not fill. I cannot doubt that Professor Voelcker 

 indicates the proper remedy for this in the application of 

 lime, of which these soils are comparatively deficient. It 

 would consolidate the soil, render the wheat less liable to be 

 hoven, and help to strengthen the straw, and render the growth 



