WATER SOILS. 21 



;ill'iilf:i, tlie iiioiv humid the soil occiiijicd by it. (S) The j,M-c:itcr tlic yield of alfalfa, 

 the drier the soil under it. (!») The une(iual development of alfaha and elover on a 

 Held depeuda at least in i)art on the ineciuality of the distrilmtiou of the soil mois- 

 ture. (10) An increased water content in the soil occupied by alfalfa or clover 

 furthers a good development and growth of these plants. (11) Deep plowing 

 increases the moisture of the soil. (12) The beneficial effect of the increase of mois- 

 ture due to deeper plowing is noticeable during 3 years. (13) The use of barnyard 

 manure increases the water content of the soil, especially in its npper layers. (14) 

 The increase of moisture in the soil from manure is noticeable even in the third year 

 after its use. (15) Under beets there is more moisture in the soil than under barley. 

 A like increase of moisture is noticeable in the year following the beet ciilture. This 

 is one of the causes of the increased yields of alfalfa in the first years of its culti\ati< >n 

 after l)eets. — i*. fikemax. 



Report of the Kherson Gxperiment field for 1899-1900, F. 15. Yaxovchik 

 {Kherson, 1902, vol. 9, -pp. Hi; ''''''• '» Pochvovedcnle [La Pcdoloyie'], 4, {1903), No. 4, 

 pp. 4S3, 434). — The most interesting experiments described in the report are th(jse 

 relating to the evaporati(jn of water l)y summer wheat as affected by the fertilizing 

 and the different moisture content of the soil. Some of the results are as follows: 

 (1) In the case of a large water content in the soil tillering begins earlier than 

 when the moisture is low, while the other phases of development set in in the c(jn- 

 verse order; (2) a high moisture content increases the effect of fertilizing; (3) the 

 straw and the root system develoj) more strongly with the increase of moisture 

 while the head becomes shorter. Regarding the amount of "water evaporated per 

 unit of crop, the following data are given: (1) AVhen the moisture content in the 

 soil was small (10 per cent) 500 units of water were required jier unit of yield, 

 although the presence of nitrogenous fertilizers lowered this proportion; (2) with a 

 medium moisture content (14 per cent) of the soil the plant evaporate more water; 

 (3) with oi:)timum moisture (18 per cent) of the soil almost no further increase of 

 evajioration took place, in the absence of fertilizer, but the evaporation strongly 

 increased in the presence of nitrogenous fertilizer. The i)rogress of evaporation 

 during the period of vegetation was as follows: (1) In the first period of develoj)- 

 ment (until the middle of ^lay) the daily consumption of water in the vessels with- 

 out fertilizer (nitrogenous) was greater than in those with fertilizer. (2) Aljoutthe 

 middle of May the fertilized wheat began to grow raj^idly and overtook that without 

 fertilizer and at the same time consumed considerably more water. (3) The maxi- 

 nunn consumj)tion of water took place during the last days of May. This was the 

 period of heading and flowering. In the i:)resence of a large ^^tore of water and fer- 

 tilizer in the soil these processes continue for greater lengths of time during which 

 the water consumption continues to be intense. (4) The increase of the consum])- 

 tion of water corresponds not only to the increase of the evaporating surface (cor- 

 respon<ling to the larger growth of the plant) but also depends on the fluctuations 

 of the temperature of the air. — r. kiremax. 



Brack land in relation to irrigation and drainage, V. M.vcOwan {Ayr. Join-. 

 Otpe Good Hope, 33 {1903), No. 5, pp. 573-581). — This article discusses the occurrence 

 and causes of the accumulation of alkali salts in South African soils, as well as 

 methods of freeing the soils from alkali. "The investigation of the conditions pro- 

 ducing J)rack in regions like ours, of restricted periodic rainfall, as compared with 

 those of countries with humid climate and greater precipitation, shows with great 

 clearness that the main difficulty is presented by the back-leaching — if it may be so 

 termed — of the limited water supply, that is, its return to the surface under the 

 powerful influence of capillarity kept going by a heated, sun-smitten surface. What- 

 ever perpetuates the downward creeping of the rainfall water, and stops its return 

 uj)ward, cures l)rackness radically. Toward this end there is one complete remedy, 

 and only one — namely, a system of complete subterranean drainage." 



