[shutt-smith] 



"ALKALI" CONTENT OF SOILS 



87 



Limits of Toxicity. 

 The present paper records the results of the analysis of five series 

 of soil groups, each series consisting of three groups representative 

 of land upon which (1) there was fair or good growth, the concentration 

 of the alkali, if present, being apparently and for practical purposes, 

 negligible, (2) there was poor growth, the crop evidently being dis- 

 tressed by alkali, and (3) there was no growth, due to excess of alkali. 

 Each series represents a separate tract of land (or field), the three 

 groups being frequently collected within a short distance of one 

 another. As in all our work in connection with the irrigation tracts 

 each group consisted of five samples: A = 0'- — 0' -5, B = 0'-5 — 1'-5, 

 C=l'-5-3'-0andD-3'-0 = 5'-0. 



Western Rye Grass. 

 Series I. Sec. 20. Tp. 9, R. 27. W. of 3rd Meridian. 



Field of Western Rye grass about 18 miles south-west of Maple 

 Creek, Sask. The land had been under irrigation for 6 years, during 

 which time the bare alkali spots or patches had increased in size very 

 considerably. Had been sown to wheat 1910, oats 1911, and seeded 

 to Western Rye grass. Crop at time of visit, July 4th, 1917, was 

 only fair on better parts of field, the plants being from 4 to 6 inches 

 in height. Soil a dark brown, almost black, moderately light loam, 

 of good quality; sub-soil of heavier character, a dark grey to yellow 

 grey clay with a little sand. Water table, from 3 to 5 feet, according 

 to contour of land. One group of samples taken from a bare spot, 

 the second in sparse and meagre growth, about 15 feet distant, and the 

 third in the best growth, about 80 feet from the same point of collection. 



Western Rye Grass. 

 Series 1. Sec. 20, Tp. 9, Rg. 27, W. of 3rd Meridian. 



