18 



EXPERIMENT STAl?^^ ^^30ED. 



cMorids, sulphates, bicarbonates, and carbonates of sodium, potassium, calcium, 

 and magnesium in varying proportions. 



The nature of the dry farm soils of Utah, J. A. Widtsoe and R. Stewart 

 (Utah Sta. Bui. 122, pp. 271-288). — Studies of the origin, physical properties, 

 and chemical composition of the soils of the dry farms in Juab, San Juan, 

 Sevier, Iron, Tooele, and Washington counties are reported and discussed. 



"A study of the results reported . . . clearly indicates that the soil fertility 

 problem on the dry farms is clearly one of the addition of organic matter 

 (containing nitrogen to the soil for the purpose of liberation of the plant food. 

 With the exception of the San Juan County section, there is no possibility of 

 the soil becoming acid in nature. The soils are all abundantly supplied with 

 sufficient potassium for wheat production, which will undoubtedly be the chief 

 crop produced on the dry farms. The soils are well supplied with phosphorus 

 and it is not probable that the addition of this element would be profitable in 

 the immediate future. Further investigation should be carried on regarding the 

 nitrogen and humus content of our dry farm soils. And in the meantime every 

 occasion should be taken to plow under the stubble and to make better utiliza- 

 tion of the straw stacks on the farm." 



The soil of the Southern Utah Experiment Station, J. A. Widtsoe and R. 

 Stewaet {Utah Sta. Bui. 121, pp. 2Jt3-268. flg. i).— This soil is very sandy in 

 nature and contains crystallized gypsum. The average composition of the first 

 and third foot of the soil is given in the following table : 



Average composition of the soil. Southern Utah Experimental Farm. 



Soil constituent. 



Insoluble residue , 



Potash, K2O 



Soda, Na^O 



Lime, CaO 



Magnesia, MgO 



Sulphuric acid, SO3. . . 



Iron oxide, Fe203 



Alumina, AI2O3 



Phosphoric acid, P2O5 

 Carbon dioxid, CO2. . . 

 DifEerence 



Surface foot. 

 (Average of 

 15 analyses.) 



Per cent. 



77.93 



.58 



.36 



5.37 



2.54 



1.01 



2.36 



3.45 



.17 



4.49 



1.74 



Total. 



Humus 



Nitrogen... 



100. 00 

 0.580 

 .029 



Third foot. 

 (Average of 

 8 analyses.) 



Per cent. 



77.60 



.49 



.15 



5.20 



2.57 



1.44 



2.22 



2.34 



.17 



3.48 



4.34 



100. 00 

 0. 4900 

 .0214 



These results .?how that the soil contains a normal amount of potash, but a 

 low amount of phosphoric acid, and is extremely deficient in humus and nitro- 

 gen, the latter being the limiting element of plant production. The soil con- 

 tains a good supply of the other essential elements of plant food and is well 

 supplied with calcium carbonate. It contains a high percentage of magnesia. 

 It also contains small amounts of sodium chlorid. sulphate, and carbonate. 

 Although the percentage of water-soluble salts is high, four-fifths of this 

 " alkali " is gypsum. The needs and management of the soil are discussed. 



Two volcanic loams of Japan, T. Seki (Landw. Vers. Stat., 79-80 {1913), 

 pp. 871 890). — Studies of the mineralogical composition, particularly as regards 

 the presence and composition of zeolitic compounds, of the volcanic loam forma- 

 tions of Tokio and of Morioka, Japan, indicated that allophane-like compounds 

 were present in the Tokio loam, probably a decomposition product of plagioclase. 

 The principal decomposition product of the soil was an argillite-like substance, 

 composed mainly of colloidal material and iron oxid. 



