H4 RELATIONS OF SOIL TO WATER 



On June 17 and 20, the excess of water in the first 2 feet 

 of the cultivated soil amounted to i inch. The influence of 

 cultivation did not apparently extend to the third foot till 

 after this date. 



For this method of preserving water to yield its best results it 

 should be commenced early. The soil at the end of winter is 

 generally nearly saturated with water ; if this water is to be 

 preserved for the use of a crop the cultivation of the surface 

 should be commenced as soon as a loose pulverulent layer 

 can be obtained. The most effective plan according to King 

 is the inversion of a thin layer of the surface soil ; but as this 

 loose surface layer requires to be renewed after each heavy 

 rain, the use of a cultivator, horse-hoe, or grubber, is probably 

 the most practical proceeding. In the United States it is 

 usual to cultivate the soil in this manner between the rows of 

 maize till the height of the crop forbids further action. 



Evaporation from the soil will be more effectually checked 

 by covering it with a mulching of manure or straw than by 

 the method just described, but the system of mulching is one 

 for the garden rather than the field. Trials made at the 

 Experiment Station, New York (New York >jth Rep., 1 80), will 

 illustrate this part of the subject. An uncropped loam, kept 

 free from weeds, was divided into plots ; each plot was in 

 duplicate. One pair of plots remained untouched ; three 

 others were cultivated to various depths ; a fifth was covered 

 by a i -inch mulch of short oat straw. The experiment began 

 in May, and continued till the end of September. Samples of 

 soil i ft. in depth were taken every week by boring, and the 



Stones of porous material, as many limestones, are less effective ; indeed 

 slight showers may be held in such cases by the stones, and the water after- 

 wards evaporated without benefiting the soil. 



