816 EXPEEIMENT STATION EECOED. 



usually (HI the gently sloping- southern declivities or on the slight 

 depressions of the steppes. Sometimes these areas occupy dozens of 

 square kilometers and contain saline lakes, but more frequently they 

 are scattered over the steppes in small spots. In a vertical section of 

 a chernozem alkali soil there are seen: (a) The upper horizon, black, 

 dark gray, dai'k brown, oi* gray, sometimes homogeneous, sometimes 

 pervaded by a whitish dust; from 1 to 3 dcm. deep; (b) a light gray or 

 whitish horizon. 1 to 3 dcm. deep (sometimes almost absent), merging 

 into (c) a brownish or vellowish compact and sticky clay. 



On the surface of the alkali soil, especially after a rain, appear 

 efflorescences or crusts consisting of whitish siliceous powder and 

 minute saline crystals. The content of humus in the upper horizon 

 is in general much less than in the adjacent chernozem, but sometimes 

 reaches 8 per cent and more. The water extracts are colored light 

 cinnamon or light cherrv from the alkaline humates in solution. The 

 solubility of the hunuis reaches one-seventieth in the upper horizon 

 and one twenty-tifth in the second horizon (b), /. t.. it is twice or three 

 times as great as in the chernozems. This is due to the greater humid- 

 ity of the alkali soils and brings them into close relation with the soils 

 of the podzol type. The whitish color of the lower horizon and the 

 siliceous dust of the efflorescences and crusts is due to the same cause. 

 Of the mineral salts soluble in water in the alkali soils of the chernozem 

 zone there occur sodium carbonate, sodium sulphate, sodium chlorid, 

 calcium sulphate, magnesium sulphate, and calcium bicarbonate. Many 

 alkali soils are marly. The total amount of salts extracted by water 

 varies according to Kostichev and others from 0.5 per cent to 5 per 

 cent and more. With regard to physical characteristics, the alkali soils 

 of the chernozem territory are distinguished by becoming very com- 

 pact and hard upon drying. 



The alkali soils of the dr^' steppes and of Turkestan are mosth' 

 yellowish and brownish in color, like the zonal soils which surround 

 them, but dark colored alkali soils are also met with. The white 

 incrustations consist of sodium sulphate, sodium chlorid, magnesium 

 sulphate, calcium sulphate, and carbonates. Extensive alkali deserts 

 without an}' cultivation whatever occur, as well as saline nuid flats. 



In general the alkali lands of European and Asiatic Russia bear a 

 close resemblance to those of Hungary, India, Aral)ia, the western 

 States of North America, Argentina, Australia, and other level and 

 dry regions. 



//>n/n(.s-raIcareo}(.^ soiJs. — The soils which are formed fi-oni lime- 

 stones and marls are frecjuently skeleton soils and contain little humus, 

 especially if distril)ut('d over steep river ])anks and along ravines, but 

 from the sume parent rocks — soft limestones, chalk, and chalky marl — 

 originate gray and dark gray soils, sometimes very rich in hunuis. In 

 the southern part of Poland they attract especial attention, being in 



