326 SOILS 



returned to it except the stubble and roots of the 

 grain, the roots of the potatoes and a few 

 weeds. For fifty years my father and I have been 

 exhausting the soil of its vegetable matter. No 

 wonder the soil gets cloddier and harder to work 

 every year; it needs more of this material to sepa- 

 rate me particles and make it looser and more 

 fibrous. I know why it suffers more from drought 

 than it used to it has not enough of the spongy 

 material in it to hold the moisture. I am going 

 to try growing some crop to plow under and decay 

 in the soil. I believe it is the lack of this material 

 more than the lack of plant food that reduces my 

 yields." 



The farmer who made these remarks to me, 

 about eight years ago, has since then more than veri- 

 fied the accuracy of his conclusion. Each year 

 he now devotes a portion of his farm to clover, 

 vetch, field peas, rye, rape, or some other crop that 

 fits into the rotation, and plows under the herbage. 

 His soil is growing richer and his fertiliser bill has 

 been cut in two. Soil that formerly was lumpy, 

 "run together," and baked is becoming mellow 

 and in good heart; its texture has been improved 

 by the addition of humus. 



This farmer is only one of thousands who now 

 make use of "green manure," as such a crop 

 is called, for the improvement of their lands. I 

 once heard a speaker at a Farmers' Institute 

 say: "The key to maintaining the fertility of 

 the soil is to have plants decaying in it all 

 the time, as is the case in uncleared land." 

 This statement of the problem is forceful and 

 practical. He did not mean, of course, that 

 numus alone can maintain fertility. No amount 

 of green-manuring can enrich a soil in the 



