WHEAT IN WESTERN CANADA 43 



until the following spring. Thus the prairie grasses, etc., 

 are prevented from growing and using up moisture, and 

 the moisture is stored and conserved in the newly-broken 

 land. 



After one or more crops have been taken from the land 

 subsequently to new breaking or summer fallowing, the 

 land is prepared for the next crop by fall or spring plow- 

 ing, by disking, cultivating, or, in some cases, by seeding 

 on the untilled fields without any previous cultivation. 

 Fall plowing is the most common practice but, in the dryer 

 areas, spring plowing is sometimes carried out instead. 

 The disadvantage of spring plowing arises from the delay 

 which is involved in putting in the seed : spring plowing 

 necessitates late sowing, late sowing is followed by late 

 ripening, and late ripening of the grain increases the dan- 

 ger to which the crop is exposed from early fall frosts. In 

 some areas where plowing is not considered necessary but 

 where some form of surface tillage is deemed advisable, 

 the stubble fields are disked or cultivated either in the fall 

 or the spring. Sowing on untilled stubble fields, while 

 not a general practice, is frequently carried out on land 

 which is free from grass and weeds and the surface of 

 which in the spring is found to possess a natural mulch 

 or loose top layer of soil forming a natural seed-bed. In 

 some districts, where untilled fields are sown, the stubble 

 which holds the snow during the winter is burned off in 

 the spring before seeding. 



Until recently, but little or no attempt was made to 

 apply manure or fertilizers to the land, and the grain fields 

 were cropped year after year without anything being added 

 to them. Of late, however, with the introduction of mixed 

 farming, farm-yard manure has come to be more commonly 

 used, particularly on the lighter soils. The manure is 

 spread upon the summer fallow, root-grounds, etc., some- 



