266 



Milling Properties of Oats. 



[august, 



Six varieties out of eight produce more meal on the clay 

 than on the gravel, and the difference is considerable — e.g., the 

 4 per cent, difference in favour of Potato at Tipperty means 

 that a crop of 56 bushels per acre is worth 12s. to 14s, more 

 to the miller than the same number of bushels grown at Echt. 



General Conclusions. — The experience we have gained in 

 conducting these experiments has convinced us that the 

 conditions upon which the milling properties of any variety, 

 or of different samples of the same variety, depend are many ; 

 and we have been led to draw the following general conclusions 

 partly from the experimental evidence and partly from theory. 

 To avoid confusion, it is convenient to consider the milling 

 factors first, as affecting different samples of the same variety, 

 and, second, as affecting samples of different varieties grown 

 under similar conditions. 



The same Variety. — We conclude that the proportion of 

 meal obtainable from oats of the same strain will vary according 

 to two sets of causes which may be distinguished as primary 

 and secondary. The primary causes are soil, season, manuring 

 and dressing of grain. The secondary causes assert themselves 

 when the primary causes have acted equally on all samples, as 

 moisture, maturity and thickness of husk. 



The Soil. — -Experience shows that clay soils grow oats of 

 high milling power, and peaty soils grain of least value in that 

 respect. The difference is probably due to the thinner husk 

 and better matured kernels of clay-grown oats. 



The Season. — A dry season is favourable to meal production, 

 as the grain contains less moisture and is better matured — 

 i.e., the kernel is larger in proportion to the husk. 



Manuring. — Excessive nitrogenous manuring tends to thicken 

 the husk, delay ripening and increase the percentage of water 

 in the grain. Phosphates and potash — especially the latter — 

 appear to increase the proportion of kernel, and certainly 

 accelerate ripening. 



Dressing. — If oats are not carefully sized or graded, loss 

 occurs from the following causes : — {a) Grains of unequal size 

 do not dry uniformly ; (b) in shelling badly dressed samples, 

 the larger grains are broken and the smaller escape ; (c) very 

 small grains are blown among the husks. 



The difference in out-turn of meal between well-dressed 



