soil, SESSION. 155 



pressed in acres per cubic foot, and in the three cases chosen for illus- 

 tration, the coarse sandy soil possesses no less than one-sixth the loam, 

 I, and the finest clay soil more than 5 acres of soil-grain surface for 

 each and every cubic foot of such soil in the field. These areas aggre- 

 gate for the surface foot and per acre of field more than 10, 60 and 

 300 square miles, respectively, for the coarse sandy soil, the loam and 

 the finest clay type. Twelve hundred, two hundred and forty and forty 

 square miles of pasturage in the four feet in depth of the root zone 

 surface, per acre of crop, seems like an enormously extravagant allow- 

 ance upon which to grow grass and grain and vegetables and fruit, and 

 yet it is what nature has provided. Verily, every farmer is a multi- 

 millionaire in the acres of internal soil surface from which he wins his 

 harvest ! And now I must repeat once again that it is over such vast 

 areas as these that the soil moisture of the effective root zone is spread, 

 from which it dissolves the mineral ingredients it carries and against 

 which both these and that which comes from the decay of the organic 

 matter is stored for the use of crops. 



With these conceptions of the differences between soils of differ- 

 ent types and of the manner in which the soluble conditions of the plant 

 food elements accumulate so as to be appropriated by crops, the great 

 importance of a deep and abundant incorporation of organic matter in 

 the soil can be appreciated ; because through it decay takes place in 

 contact with a much larger soil surface, more room is given for the soil 

 organisms to work, the plant food materials produced may be concen- 

 trated upon and retained by a much larger surface, and there is greater 

 opportunity for the roots to come in contact with the plant food devel- 

 oped and stored. 



Deep incorporation of organic matter is accomplished by a thorough 

 turning under of the roughage of the fields, using the jointer and chain 

 where necessary ; through frequent moderate and occasional deep turning 

 down of both stable and green manures ; by growing in rotation the 

 deep-rooted leguminous species, together with the densely and deep- 

 rooted grasses. No form of organic matter for incorporation in the soil is 

 so valuable as stable manure. It is so because it has been placed in 

 superlative physical condition by being finely ground and because it is 

 doubly charged with the most available of plant food materials. The 

 great problem is to get it incorporated with the soil deeply and thor- 

 oughly while it is yet at its full strength. To throw it about to weather 

 in the rains and the sun is no less irrational and but little less wasteful 

 than would be a similar practice with the hay and the grain from which 

 it was produced. Excessive applications to the soil, too, like the over- 

 feeding of live stock, is literally throwing money away, besides making 



