24 THE SOIL OF THE FARM. 



tiling injurious to vegetation ; sucli as an excess of organic 

 acids, or the presence of small quantities of sulphate of 

 iron or other poisonous ingredients. It may also be due 

 to an excess of otherwise valuable ingredients, such as 

 organic matter, sand, lime, or even clay. In the strict 

 meaning of the word no soil, unless it contains some 

 substance poisonous to plants, is absolutely barren ; but 

 one may call a soil barren which will not produce such 

 plants as the farmer cultivates. Such a soil may be 

 made fertile by adding to it the substances in which it is 

 deficient ; but if this cannot be done except at a cost as 

 great or greater than that for which fertile soil can be 

 procured, the soil may be regarded as practically worth- 

 less. 



Natural and acquired Fertility. — The distinction here 

 must not be forgotten. Sir James B. Lawes in discussing 

 this subject, writes thus : '^ The natural fertility of a soil, 

 whether high or low in degree, is, comparatively speak- 

 ing, a permanent quality ; it can only be injuiiously 

 affected by the continuance of an exhaustive system of 

 cropping for a long period of time ; it is the property of 

 the landlord ; and, excepting in the case of very light 

 soils, it is the chief element in determining the rent- 

 nature of the land. Acquired fertility, or ^condition,' 

 as it is termed, is a quality distinct from the natural 

 fertility of soil ; it is due to the accumulation within the 

 soil of manure matters which may be withdrawn or re- 

 duced by cropping within a comparatively short period 

 of time. It is a quality dependent on the capital ex- 

 pended by the tenant in the purchase of cattle food or 

 manures, and is, therefore, his property." But, as the 

 proverb has it, " Nature passes Nurture ; " and a soil 

 which is naturally fertile is better than one which is fer- 

 tile only by the help of manure. 



''The fertility of a soil may be expressed," according 



