50 BRITISH HUSBANDRY. [Ch. IV. 



and lucerne, for instance ; even red clover will strike down to nearly tliree 

 feet if the soil be a fertile loam ; and some of our commonest vegetables, if 

 it be friable or sandy, push their tap-roots to about the same depth. But 

 as the land is chiefly destined for the production of grain, its value is rather 

 to be considered according to its capability for the growth of corn than for 

 that of any particular species of green crop. 



It may be observed by the mere naked eye, that if the land be of a free 

 nature, the roots of wheat will penetrate as far as eight inches into the 

 earth ; and when sown on the crowns of ridges, they have been found in 

 rich soils at the depth of twelve ; though that probably arose from the greater 

 influence of the atmosphere, for they do not reach to the same depth on 

 level ground. The seed is usually sown at about two inches deep ; conse- 

 quently, the roots may be ten inches long. We may, therefore, assume the 

 depth of twelve inches as the utmost vegetative limit of corn land. 



If the plants lie close together, they are disposed to penetrate more deeply 

 into the earth than when they are wide apart ; for it may be remarked that 

 the roots of corn avoid each other, aiid push their strongest shoots into 

 those spots where they have most room to spread ; but if the seed be thickly 

 sown, they are then forced to strike their roots perpendicularly, instead of 

 laterally, into the ground. Still, however, this must depend upon the 

 nature of the land ; for if the subsoil be sterile or tenacious, the roots then 

 either meeting opposition, or not finding nourishment, must again seek the 

 upper stratum. There, they become matted together, and, each contending 

 for the share of nutriment of which it has been deprived, the weakest are 

 often seen to perish ; which in a great measure accounts for that partial 

 failure which frequently attends corn crops at the very height of the season. 

 Provided the soil be open and tolerably fertile, the nearer its depth ap- 

 proaches to that which we have stated to be its vegetative limit, the greater 

 number of plants may it therefore be supposed capable of furnishing with 

 support*; and, if attentively observed, a material difference will be found 

 between the nutritive properties of land of a deep staple, and that which is 

 more shallow, although the quality of both, when tried in equal quantities, 

 may be the samef. When deep, it also possesses the great advantage of 

 suffering less either by extreme heat or by wet, than when thin ; and the 

 corn being supported by a greater depth of root, which probably affords 



=^ A remarkable iustauce of this is mentioned in the Bedford Report, in which it is 

 stated " that a road having been made across the ends of some ridged lands in the parish 

 of Ridgemount, the cultivated soil of the ridges was cast into the hollows. The field was 

 afterwards sown with barley, and tlie scattered corns which grew where the soil was accu- 

 mulated in the ancient furrows formed a remarkable contrast with the rest of the field. 

 The produce of the barley crop was little more than three quarters per acre, while that 

 which grew on the same poor soil, accumulated, perhaps, a foot deep, was remarkably 

 luxuriant, many of the corns producing from ten to twenty stalks, and the cars large in 

 proportion." An effect which the reporter ascribes to no other cause than the depth of the 

 soil. — p. 277. 



f Von Thaer calculates this difference in proportionate degrees in land which contains 

 a. vegetative stratum of soil of four, six, eight, and twelve inches in depth ; provided, of 

 course, that it be all of equal quality. If, therefore, each seed were to produce a plant, it 

 would follow that ground which contains eight inches depth of fertile mould, might be 

 sown with double the quantity of that which consists of only four inches. He, however, 

 admits that this principle cannot be carried to that extent, because the action of the 

 atmosphere must ever afford such a superiority to the surface, that a cubic foot of mould, 

 if divided into two square feet, will always produce a greater number of plants than if the 

 seed were sown upon one foot superficial; but he assumes the value of the land to be 

 increased in the proportion of 8 per cent, for every inch of mould beyond the depth of six 

 to ten inches, and to be diminished, in the same proportion, from six to three inches in 

 soils of a thinner staple.— /"rwa/jes Raisoiinis (C^jricuUvre, vol, iii., p. 138. s. 735, 



