ORIGINALLY PUBLISHED | MAY 16, 1912 | THE FARMER'S ADVOCATE
The increase in soil productivity, if such is ever made, must depend largely on the four following factors, cited by C.R. Barns of Minnesota Agricultural College, viz: (1) A liberal and persistent use of fertilizers; (2) the careful selection of seed, which, if persisted in year after year will of itself result in a great increase in yield; (3) a systematic rotation of crops; (4) better cultivation and tillage. The first of these factors involves the keeping of all the live stock possible, and the saving of every particle of manure. Add to this the frequent plowing under of green crops, and the enrichment may equal that attained in Europe and elsewhere by the use of artificial fertilizers. The cost of such fertilizers is always to be taken into consideration in comparing the production of European with that of home lands. The important of seed selection is now fully recognized. This and the other two factors are within the control of practically every farmer bent upon securing a big crop.
The importance which is given to farmyard manure and green crops as fertilizers is worthy of note. Organic nitrogen can only be added to the soil by the use of these materials. Humus is one of the greatest acting factors in soil fertility. Humus is decaying plant material, or, in other words, barnyard manure or green crops plowed under. These two, supplemented with artificial or mineral fertilizers, and used in sufficient quantity, insure any farm against deterioration in fertility, provided the other three conditions herein enumerated are carefully carried out.