314 Cultivation by Deep-rooting Plants. 



the crops, though you would only have added to the land 

 531b. of nitrogen, 22lb. of phosphoric acid, and i6Lb. of 

 potash, but then, he adds, you would have supplied these 

 substances in an available form. If, then, these constituents 

 are almost dead in what is called, and, practically speakings 

 is, an exhausted soil, it is owing to the want of that humus 

 which is the very soul of the soil. In other words, give to it an 

 abundance of decaying vegetable matter, which, when alive, 

 has dissolved and so turned into available plant food the 

 otherwise inert constituents present, and the soil lives ; with- 

 draw this vegetable matter, or reduce it to a low ebb, and the 

 soil becomes almost lifeless. And besides the chemical and 

 physical evils that thus arise, there follows a long train of 

 consequential results, almost any one of which is a serious 

 drawback to agricultural success. I have practically experi- 

 enced them all, both in the jungles of Mysore and on a pro- 

 perty on the slopes of the Cheviots. The exact parallel that 

 exists between experiences so far apart may be interesting 

 and perhaps useful as an illustration. 



Many years ago two planters, of whom I was one, cut 

 down the forest and planted coffee. For a considerable- 

 number of years all went well. The crops were good, 

 the land was easily worked, and diseases amongst the 

 coffee existed only in an infinitesimal degree. But as time 

 went on the decaying vegetable matter diminished, or, in 

 other words, the soil became more and more mineralised. 

 Then the crops declined, diseases spread amongst the 

 coffee, and the land became more difficult and expensive to 

 cultivate, and quickly hardened after being cultivated. 

 The agricultural chemist was then called in, and he 

 assured us that all we had to do was to restore the 

 elements removed by the crops. But all the artificial 

 manures we applied could not restore the soil conditions 

 with which we started, and therefore did not enable the 

 coffee to contend effectually with disease and adverse 

 seasons. In the end we were obliged to go back to 

 nature — to the soil foundations she laid for us centuries ago 

 — and apply to the land topsoil from the adjacent forest 

 land, swamp soils, and other soil admixtures, in order to 



