CARBON IN THE SOIL. 23 



short, the soil has become dead. It hardens, closes 

 its pores, and no further produces profitable crops. 

 These, indeed, are dire results of the exhaustion of 

 carbonaceous matter. 



Nature has a remedy, when man does not inter- 

 fere. Weeds, shrubs, trees spring up, catch the 

 carbon floating in the air, and by their decay deposit 

 carbonaceous matter on top of the soil (leaf mould, 

 humus), and thus in the course of many years fur- 

 nish a new supply. The natural process of recuper- 

 ation is a lengthy and tedious one. The soil tiller 

 can hasten it, and restore life and activity to the 

 soil by the reintroduction of abundant carbonaceous 

 matter; in other words, by application of stable 

 manure or peaty substances, or by plowing under 

 crops, such as clover, southern black peas (cow 

 beans), lupines, weeds, etc. 



On the whole I think that carbon occupies a posi- 

 tion of greater importance in the economy of plant 

 growth and profitable plant feeding than is assigned 

 to it by a majority of farm writers, of high as well 

 as low degree, or than might be inferred from the 

 fact that no quotable value is conceded to it, or that 

 it is entirely left out in the computation of commer- 

 cial values of manures. This subject will be taken 

 up again further on; for it is plain that satisfactory 

 cropping cannot usually be continued for any length 

 of time, unless the natural condition of the soil is 

 maintained by restoration of the consumed vege- 

 table matter through one or the other of the pro- 

 cesses named. 



