32 ON THE USE OF LIME, MARL, AND SHELL-SAND. 



To keep land in good condition, we must, as a general rule, add 

 as much of everything as we carry off in the produce. The 

 judicious farmer, therefore, will apply all the materials which 

 are demanded by the increased produce in larger quantities than 

 by a scanty crop ; and this he does by liberally adding manure 

 to the land, and not merely by using lime as a substitute for 

 manure. If manure is liberally added to limed land, no ex- 

 haustion need to be feared. 



On the other hand, the neglect of this principle, which ought 

 to be kept in view by every one cultivating land, must be at- 

 tended with a more speedy exhaustion than when no lime is 

 used ; for we cannot constantly take out of the land a number of 

 fertilizing substances, and add only one material, without im- 

 poverishing it. 



On the Crops most benefited by Liming. 



We have stated above that all cultivated plants require lime 

 as an essential article of food, without which they cannot come 

 to perfection, and it is therefore evident that it will increase the 

 produce of all crops on soils naturally deficient in this substance. 

 But as lime exercises several important functions in relation to 

 the vegetable processes, we may expect that its application to 

 some crops will be characterised by a more marked effect than to 

 others. Practical experience confirms this supposition, for it is 

 well known that liming not only improves the quantity and 

 quality of some crops in an especial manner, but that it alters as 

 well the natural produce of the land, by killing some kinds of 

 plants and favouring the growth of others. 



The crops which are especially benefited by liming are : 

 clover, rye-grass, and natural grasses ; sainfoin, peas, beans, and 

 vetches ; turnips. 



The effects of lime upon clover and rye-grass are strikingly 

 beneficial ; and for this reason perhaps on no description of 

 crops is lime applied so advantageously as upon white clover and 

 artificial grasses. It causes white clover and rye-grass to thicken, 

 and to produce a closer sole every succeeding year the land 

 remains in pasture, and thus contributes greatly to enlarged crops.* 

 Not only is the quantity of the clover crop increased, but its 

 quality is also materially improved. Clover and rye-grass, when 

 grown on limed land, are far more juicy and nutritious than when 

 grown on unlimed land. 



On many soils it is indeed impossible to cultivate, economi- 



* Lime, when applied as a top-dressing upon dry lands that have not even 

 been cultivated, on Exmoor, has the magical effect of producing white clover in 

 quantity, without its being sown. R. S. 



