430 EUROPEAN AGRICULTURE, 



ever, must all be deemed exceptions ; and the general rule in 

 England, where the soil admits of it, and manure is abundant, is 

 that of rather deep ploughing. Five or six inches is the average 

 depth ; in many cases, much more than this. The loam, or 

 vegetable mould, is, without question, the great source or me 

 dium of nourishment to the plants. Be it more or less deep, it 

 is always safe to go to the bottom of this, and, by gradually 

 loosening a portion of the subsoil, or lower stratum, and incor 

 porating it with the mould, and rendering it accessible to the 

 air and light, it acquires the nature of mould, and the whole 

 arable surface is enriched. The deeper the soil, the more 

 deeply the roots are permitted to descend, and the more widely 

 they are enabled to spread themselves, unless they penetrate a 

 substratum unhealthy from wet or the too great prevalence of 

 some unfavorable mineral substance, so much the more luxu 

 riant and productive is the vegetation likely to prove. The 

 depth to which the roots of plants will go down in search of 

 food or moisture, where the soil is in a condition to be pene 

 trated by them, is much greater than a superficial observation 

 would induce us to suppose. It is confidently asserted that the 

 roots of some plants such, for example, as lucern and sainfoin 

 go to a depth of fifteen, twenty, and even thirty feet. This 

 seems scarcely credible. Red clover is known to extend its 

 roots to the depth of three feet, and wheat to the depth of two 

 or three feet, where the condition of the soil is favorable to their 

 extension. Von Thaer, the distinguished agriculturist, says, 

 &quot; he has pulled carrots two and a half feet long, the tap-root of 

 which was probably another foot in length.&quot; The tap-root of a 

 Swedish turnip has been known to extend thirty-nine inches ; 

 the roots of Indian corn full six feet. These statements may 

 appear extraordinary ; but, by the free and loose texture of the 

 soil, it is obvious a good husbandman will give every opportunity 

 for the roots and their extremely fine fibres to extend themselves 

 as far as their instincts may prompt them. 



Next to the depth of ploughing, the width of the furrow-slice 

 is to be considered. This, of course, depends mainly upon the 

 construction of the plough. A plough with a wide sole or base, 

 in the hands of a skilful ploughman, may be made to cut a nar 

 row furrow-slice ; but a narrow-soled plough cannot be made to 

 cut a wide furrow-slice, though it may sometimes appear to do 



