THE BEST SOIL 



139 



the soil to hold capillary water — that important 

 quantity which should be conserved by all reason- 

 able means. 



It must not be doubted that for sub-drainage 

 purposes humus is essential in heavy soils. The fol- 

 lowing table is compiled to graphically illustrate 

 this truth : 



Kind of soil. Water percolation in 12 hours. 

 Clay 1.10 inches 



Clay loam is admittedly the best soil for fig trees, 

 but it should receive liberal additions of humus 

 from cover crops, or manures. Compared with oth- 

 er soil matter humus absorbs water like a sponge, 

 moisture soaking" from fiber to fiber, part to part 

 until all is rapidly filled. The above table states 

 facts about capillary water- gravitational water 

 passes through sand in a short time. A combination 

 of clay and humus has those qualities which distin- 

 guish it as an absorbent and the best texture for 

 moisture retention. 



But if there is a high content of humus, moisture 

 passes off the surface more rapidly, for the same 

 reason that it percolates so quickly. Its percola- 



Silt . . . 

 Sand . 

 Humus 



16.82 inches 

 118.91 inches 

 193.40 inches 



