2 3 



TABLE XIII. 



Estimates of the yield of various Crops in Manitoba. 



Summary of Statistical Eeturns seven years, 1876-1882. 

 Quantities in bushels per acre. 



The above estimates are founded on the reports of numerous farmers, 

 and it is seen that the average yield of wheat for seven years (1876- 

 1882) is assumed to be twenty-nine bushels. This is, however, doubtless 

 too high, even for exclusively virgin prairie soils, under the condition 

 of cultivation incident to new settlement ; and the result is probably 

 accounted for by the fact that the records come chiefly from the more 

 intelligent and better farmers. From returns since supplied to me 

 from the Department of Agriculture at Ottawa, the average produce of 

 wheat in Manitoba was, in 1880, 20.1 bushels, and in 1882, 24.0 bushels, 

 instead of 29 and 32 bushels as above; whilst the average produce in 

 1883 is estimated at 21.8 bushels. 



In connection with this subject of the average yield of wheat of differ- 

 ent countries, it will be of interest to contrast the condition of soils of 

 very different history, as to their percentage of nitrogen, and, so far as 

 we are able, of carbon also. 



Table XIV. (see next page) shows the characters in these respects of 

 exhausted, arable soils, of newly laid down pasture, and of old pasture 

 soils, at Rothamsted; of some other old arable soils; of some Illinois 

 and Manitoba prairie soils; and lastly, of some very rich Russian 

 soils. 



From these results there can be no doubt that a characteristic of a rich 

 virgin soil, or of a permanent 'pasture surface-soil, is a relatively high 

 percentage of nitrogen and of carbon, and a high relation of carbon to ni- 

 trogen. On the other hand, a soil that has long been under arable culture 

 is much poorer in these respects ; whilst an arable soil under conditions 

 of known agricultural exhaustion shows a very low percentage of nitro- 

 gen and of carbon, and a low relation of carbon to nitrogen. 



Finally, it has been maintained by some that a soil is a laboratory, 

 and not a mine. But not only the facts ascertained in our own and in 

 other investigations, but the history of agriculture throughout the world, 

 so far as we know it, clearly show that a fertile soil is one which has 

 accumulated within it the residue of ages of previous vegetation, and 

 that it becomes infertile as this residue is exhausted ; and enormous as are 

 the accumulations in the prairie lands of the American continent, it is 

 still desirable to postpone, rather than to accelerate, the time of their 

 exhaustion. 



