90 DORMANT FERTILITY OF UNPRODUCTIVE LANDS. 



process must have the effect, in the course of time, of fixing on 

 and near the surface the whole of a scanty supply of lime, and of 

 leaving the subsoil without any. But if there is within the reach 

 of the roots more lime than any one crop or growth of plants 

 needs, then the superfluous lime will be permitted to remain in the 

 sub-soil, which sub-soil will then be improvable by vegetable sub- 

 stances, and readily convertible to productive soil. The manner 

 in which lime thus operates will be explained in the next chapter. 

 1835.] 



Nearly all the woodland now remaining in lower Virginia, and 

 also much of the land which has long been arable, is rendered un- 

 productive by acidity ; and successive generations have toiled on 

 such land, almost without remuneration, and without suspecting 

 that their worst virgin land was then richer than their manured 

 lots appeared to be. The cultivator of such soil, who knows not 

 its peculiar disease, has no other prospect than a gradual decrease 

 of his always scanty crops. But if the evil is once understood, 

 and the means of its removal are within his reach, Jie has reason 

 to rejoice that his soil was so constituted as to be preserved from 

 the effects of the improvidence of his forefathers, who would have 

 worn out any land not almost indestructible. The presence of 

 acid, by restraining the productive powers of the soil, has in a 

 great measure saved it from exhaustion } and after a course of 

 cropping which would have utterly ruined soils much better con- 

 stituted, the powers of our acid land remain not greatly impaired, 

 though dormant, and ready to be called into action by merely being 

 relieved of its acid quality. A few crops will reduce a new acid 

 field to so low a rate of product, that it scarcely will pay for its 

 cultivation ; but no great change is afterwards caused, by continu- 

 ing scourging tillage and grazing, for fifty years longer. Thus our 

 acid soils have two remarkable and opposite qualities, both pro- 

 ceeding from the same cause : they can neither be enriched by ma- 

 nure, nor impoverished by cultivation, to any great extent. Quali- 

 ties so remarkable deserve all our powers of investigation ; yet 

 their very frequency seems to have caused them to be overlooked ; 

 and our writers on agriculture have continued to urge those who 

 seek improvement to apply precepts drawn from English authors, 

 to soils which are totally different from all those for which their 

 instructions were intended.* 



[* Confirmatory testimony. Professor Johnston affirms that lime is indis- 

 pensable to the fertility of soils, as I have done. But he goes still farther 

 than what is true, at least as to America, in the following passage: " The 

 results of all the analyses hitherto made of soils naturally fertile, show 

 that lime is universally present. The percentage of lime in a soil may be 

 very small, yet it can always be detected when valuable and healthy crops 

 will grow upon it. Thus the fertile soil of the 



