— 39 — 



a soluble condit'on continues throughout the winter. Undoubtedly, besides 

 accumulating water, these methods of culture also enricher the water 

 so'l solution with mineral matter, and raises the potential of the crop of 

 that plant wh'ch will be sown on such a field. 



The distribution of water in the soil assumes an entirely different 

 complexion under a permanent culture of corn (fig. 21). 



This farming method -the absense of rotation is adopted in sou- 

 thern Newrussian governments. On our illustration the series of cereals 

 are- winter wheat, barley, barley. There may be other combination 

 spring wheat, barley, winter wheat, barley, winter wheat and so on. The 

 order of succession is here indifferent; it is only important that neither 

 fallow nor thorough ploughed plants take any place in such farming, and 

 our local thourough ploughed culture — maize — as we have seen, uses up, 

 by harvest time, all the reserve useful water in the root layer. 



Every year the formation of the upper periodically humid layer 

 commences from autumn, generally in October, and by the time the 

 plants sown therein are ready for reaping, it has become dry, only use- 

 less water remaining. The distribution of water may be thus depicted. 

 From the surface to the lower permanent humid layer, which, under such 

 conditions cf culture, often lies deeper than on old ploughed land (160 

 to 180 cm.), the soil layer remains dry for many years, and only in the 

 superficial parts, from late autumn even from december to July, that is 

 during seven or eight month, moisture appears in a soil layer of 40 to 

 50 cm. In very moist years, like that shown on fig. 21, 3-rd year, it 

 reaches 10 cm. and more. After such an unusually moist year a part of 

 the useful water in the lower parts of the periodically humid layer may 

 not be expended; then it comes in for swelling the reserve useful wa- 

 ter in the permanent humid layer, as may be seen on fig. 21, 1-st year, 

 usually upper humid layer is, in spring not thicker than 40 to 50 cm. 

 It is moist for 7 or 8 months in the year. During that time, the proces- 

 ses of transforming mineral matter into solution, and the preparation of 

 food for the coming sowing, goes on therein. But as regard the soil 

 layer from 40 to 50 cm. to a depth of 160 to 180 cm., // may remain 

 in a dry state for many years with only useless water, and processes of 

 a chemical character will he either absent or proceed on an insii^nificant 

 scale; and no transformation of mineral salts into solution may take place. 



The soil gets impoverished through lying in dry state for a long 

 time, because more water is required to turn the quantity of mineral 

 salts necessary to the plants into solution than in rich soils, where mine- 

 ral matter is found in a soluble condition, ready for use. And the longer 

 his dried up layer of soil is without a supply of atmospheric water, the 



