[shutt] "ALKALI" CONTENT OF SOILS 237 



Group 1751. — These samples were taken from an even level 

 slope bearing a healthy stand of wheat. Nature of Soil: "A" moist, 

 light chocolate, heavy silt loam, well supplied with organic matter; 

 "B" moist, dark slate-grey, light clay loam; "C" moist, yellow-grey, 

 coarse to fine silt; "D" moist, yellow-grey, fine silt. 



Judging from the appearance of the crop the percentage of 

 saline matter present in the upper 3' is negligible; "B" contains 

 rather more than a trace of sodium carbonate, "C" an appreciable 

 amount and "D" contains more than 1 per cent, sodium sulphate, 

 which evidently at such a depth has no effect upon the vigour of the 

 crop. 



Group 1750. — This group was taken from a slope where the stand 

 of wheat was as luxuriant as could be desired but the lower part of 

 the stems showed a peculiar purple colour. Nature of soil: "A" 

 moist, dark chocolate, heavy silt loam with a good supply of organic 

 material; "B" moist, chocolate light clay loam; "C" moist yellow- 

 grey fine silt; "D" essentially the same as "C". 



The alkali content of this soil is practically the same as that of 

 Group 1751, containing only a little less sodium carbonate in "A" and 

 "B". The engineer collected this sample on account of the peculiar 

 discolouration of the wheat stem. This is the first time that this 

 abnormal appearance in wheat has been noticed and the results 

 do not indicate that it is a symptom of alkali trouble. 



Group 1749. The crop at the point from which this sample 

 was taken was poor and distressed, showing signs of marked injury 

 from alkali. Nature of soil: "A" moist, yellow to slate-grey, heavy 

 silt loam, fairly well supplied with organic material; "B" moist, 

 slate-grey, light clay loam; "C" moist, slate-grey, coarse to fine 

 silt; "D" essentially the same as "C." 



The results here correspond very closely with the analyses of 

 Group 1753. The toxic effect is evidently due to the sodium sulphate 

 and sodium carbonate present; magnesium sulphate is only in 

 negligible amounts, and while 1749B contains more sodium sulphate 

 than 1753B there is no doubt that the .06 per cent, sodium carbonate 

 in 1749B is chiefly responsible for the distressed appearance of the 

 crop. 



Group 1748^ — ^At this point all growth had ceased. The group 

 was taken from an absolutely bare spot showing alkali incrustations. 

 Nature of soil: "A" damp, chocolate coloured, heavy silt loam; "B" 

 damp, yellow-grey, coarse silt; "C" wet, yellow-grey, coarse silt; 

 D" essentially the same as "C." 



(<T\>) 



