Section III, 1922. [233] Trans. R.S.C. 



The "Alkali" Content of Soils as Related to Crop Growth 

 By Frank T. Shutt, M.A., D.Sc. and Alice H. Atack, B.A. 



(Read May 18th, 1922) 



The reclassification of certain areas within the semi-dry belt of 

 Southern Alberta into irrigable and non-irrigable lands has been in 

 progress for the past nine years. This work is under the direction 

 and control of the Reclamation Service (formerly the Irrigation 

 Branch) of the Department of the Interior, but the chemical and 

 physical examination of the soil necessary to arrive at a decision 

 as to the probability of "rise of alkali" following irrigation and the 

 general suitability of the land for cultivation under irrigation, a 

 very important phase of the work, has from the first been under- 

 taken by the Division of Chemistry of the Dominion Experimental 

 Farms System. 



This chemical work has involved the analysis of many hundreds 

 of groups of soil and the data thus amassed respecting the nature, 

 concentration and disposition of soil "alkali" have already proven 

 of immense value in the safe classification of very large tracts of 

 lands. No tract or area has been "passed" as irrigable which indi- 

 cated from the chemical or physical results that there was the prob- 

 ability of a rise of alkali and injury to the land from the application 

 of water. 



Naturally, in the course of this work many problems have 

 arisen demanding special investigation and one of the most important 

 and urgent of these has been the relation of alkali — its character, 

 concentration and disposition in the soil — to crop growth; in other 

 words the determination of the limits of toxicity to ordinary farm 

 crops. 



This investigation has been under progress since 1918, and 

 three reports have already been made to The Royal Society (1918, 

 1919, 1920) upon the subject. In these papers the nature of the 

 problem, the character of the alkali found and the urgent necessity 

 for reliable data have been explained in detail. The present paper 

 contains additional information upon the same subject and attempts 

 to correlate and interpret the results of this and previous years' 

 work. 



Series of samples have been taken and field notes made upon 

 the quality of the soil, condition of the crop and general methods of 



