CROP ROTATION 



J. H. GRISDALE, Director, Dominion Experimental Farms, Ottawa. 



Crops as grown by the Canadian Farmer fall far short in yield per acre of what 

 they might and what they should yield. Under extraordinary weather conditions they 

 sometimes come up to and even surpass what they really should be every year. The 

 year just passed, 1915, was of such a character. Our farmers from one end of the 

 Dominion to the other never before harvested such crops on the average as in 1915. We 

 could do practically as well every year if we only thought so and bent our effort to the 

 getting of our farms into such condition as would insure such crops. 



Extraordinary yields need not be expected every year, but crop failure would be 

 practically unknown, every year might be "a very good year," and 1915 years would 

 come just the same only not quite so strikingly. 



The key to the situation is the man. Let the man cultivate better and follow a 

 suitable rotation and crop failure becomes a myth. 



Let us consider this matter from the crop rotation side. 



Crops Needed by the Farmer 



Farmers in Canada require to grow crops likely to give profitable returns in the 

 form of seeds, that is, grain crops. At the same time they need large quantities of 

 forage, that is, such crops as yield rough feed suitable for live stock must be grown, for 

 instance, clover, timothy, roots and corn for ensilage. 



Effects of Certain Crops on Succeeding Crops 



Clover or pasture sods, when turned under, leave the soil in most excellent condition 

 for the production of forage crops, such as roots and corn. Soils which have been 

 occupied by roots or corn have lost by the end of the season a considerable proportion 

 of the humus they contained at seeding time. They are, however, compacted and in 

 most excellent shape for growing grain. The grain crops grown upon fields which have 

 been under some hoed crop the previous year are likely to give large yields of seed with 

 a comparatively small proportion of straw, the ideal condition for most profitable 

 returns. 



It is evident, therefore, that each crop affects the condition of the soil in its own 

 peculiar way, and that the condition in which a soil finds itself, after having borne a 

 certain crop, is nearly always the condition best suited for the production of some other 

 crop. 



Having observed the peculiarities of crops as to food requirements, conditions of 

 growth and residual effects upon the soil, it is evident that it should be possible to work 

 out a succession of crops where the soil condition after each would be such as best suited 

 the growth of the next. Arranging crops in this way is called "Rotation of Crops." 



ROTATION OF CROPS 



Rotation of crops means the following of one crop with another in regular and ever 

 recurring or repeated succession. Rotation comes from the word "rotare," meaning 

 "to turn round." Thence a rotation might possibly include only two crops, as for 

 instance, hay and grain alternately for a long period of time. Generally speaking, how- 

 ever, a longer rotation that is a succession of crops including a greater diversity, is 

 meant when one uses the term rotation. 



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