[shutt-smith] 



"ALKALI" CONTENT OF SOILS 



91 



Group 1604. No growth. Soil bare. The percentages of sodium 

 sulphate throughout this group exceed 2-0, an impregnation too high 

 to permit of any growth. 



(Note. — The samples in this group represent a depth only of 

 2'^8, collection below that depth being made impossible by the caving 

 in of the sides of the sampling bore.) 



Oats. 

 Series III. Sec. 17, Tp. 24, R 24, W. of 4th Meridian. 



These three soil groups were collected on July 17th, 1917, from 

 a field in oats on Farm No. 8, Namaka Colony, about 4| miles north- 

 east of Strathmore, Alberta. The area had been under irrigation for 

 some years but water had not been applied in 1917. The soil was a 

 sandy loam of good quality. The yield of oats on the best parts of 

 the field would be probably 75 bushels per acre; the portions showing 

 distressed growth the yield would probably be scarcely worth the 

 harvesting. 



Oats. 

 Series III. Sec. 17, Tp. 24, R. 24, W. of 4th Meridian. 



Discussion of Results. The alkali of this group is sodium car- 

 bonate, the characteristic salt of "black alkali," and, which, as already 

 stated, is the most injurious of all saline impregnations. The limits 

 of tolerance for most farm crops are usually placed by American 

 authorities between -05 and -10 per cent. 



The soil of group 1620 carried a good crop of oats and contained 

 uniformly to a depth of 5 feet -06 per cent of sodium carbonate, in 

 addition to trifling amounts of other and less injurious saline matter. 

 These results must not be interpreted as proving that this concen- 

 tration of sodium carbonate is harmless, but they are of pecuïïS^'^ 



a V 



