Chemical Work on Canadian Wheat. 



6 S 



newly cleared soil, since humus enhances the absorptive and 

 retentive capacity of a soil. 



In potash and phosphoric acid these soils present no striking 

 differences, though the newer soil is much the richer in lime. 

 The data, apart from the relation of humus to moisture content, 

 throw no light upon our problem.* It is interesting, however, 

 to observe that the soil with the higher percentage of nitrogen 

 produced the starchier wheat. From these results we were led 

 to believe that the explanation for the difference in composition 

 of the wheats is to be found in the widely different moisture con- 

 tent of the soils throughout the growing season, the larger amount 

 of moisture prolonging the vegetative processes of the plant and 

 delaying the maturation of its grain. This apparently allows the 

 further deposition of starch, or rather of less nitrogenous matter, 

 resulting in a more or less soft kernel.! 



If these conclusions are correct, then it might be conjectured 

 that wheat grown under irrigation in a semi-arid district would 

 be more or less glutinous according to the amount of water sup- 

 plied during the development period. To obtain information con- 

 cerning this matter, areas irrigated and non-irrigated were sown 

 in 1908 on the Experimental Farm, Lethbridge, Southern Alberta, 

 with Red Fife and Kharkov wheats. This district is usually one 

 of sparse precipitation, and one, consequently, where the methods 

 of the so-called "dry" farming must be practised in parts where 

 there is no provision for irrigation. As a rule, irrigation is 

 necessary to obtain the best yields. The season during the earlier 

 months was unusually wet, and consequently not favourable to 

 the experiment in hand, only one irrigation, July 16th, being 

 found necessary ; nevertheless, as the following data clearly show, 

 the irrigated soil, with its higher water content, produced the 

 more starchy wheat. 



Red Fife — original seed from Brandon, Man. ... 15*95 per cent, protein. 



Red Fife— grown on irrigated land ... ... ... 1370 „ „ 



Red Fife— grown on non-irrigated land ... ... 16*37 » 



Kharkov — grown on irrigated land ... ... ... 12*11 ,, „ 



Kharkov — grown on non-irrigated land ... ... 13*12 „ 



In the case of Red Fife, the wheat grown on the non-irrigated 

 and, as we shall see, drier soil contained 2*5 per cent, more protein 

 than that from the irrigated area. Similarly with the Kharkov, 

 there is a difference of 1 per cent, protein in favour of the non- 

 irrigated wheat. 



The soil-moisture determinations made at intervals throughout 

 the season are as follows : — 



* The analysis of the wheats from the fertiliser plots of the Experimental Farms 

 confirms the view that manuring has but little influence on the composition of 

 the grain. 



t Report of the Chemist, Exp. Farms, 1907-0S, pp. 135-9, 



