354 MAIZE 



chap, adoption of the best methods of preserving the fodder and 

 stover of the crop, and conserving the manure. 



(2) The ploughing-in of green-manure crops. 



(3) The suitable rotation of crops in connection with stock- 

 raising. 



(4) The use of suitable artificial manures. 



3 io. Summer Fallowing, — -Where large areas are under crop 

 on any one farm (as in many parts of the western United States 

 and parts of South America and South Africa) it is not practicable 

 to give the same amount of cultivation as would be possible on 

 a farm of smaller area. It needs too large an investment of capi- 

 tal in machinery and draught animals, not to mention the diffi- 

 culty of getting labour. But without cultivation weeds soon 

 get hold of the land, smother the crop, and greatly reduce the 

 yield. Under such circumstances summer fallowing may be 

 resorted to with advantage. By summer fallowing we mean 

 leaving a portion of the land without crop during the summer 

 season, so that it may be cleaned of weeds. Crops of young 

 weeds are allowed to grow, and are then ploughed under as 

 "green manure," or harrowed off before they get too large to 

 be pulled out or old enough to scatter seed. The latter point 

 is of great importance, for there is much truth in the old pro- 

 verb that "one year's seeding makes seven years' weeding ". 



Summer fallowing has been decried alike by practical far- 

 mers and writers on agriculture, because no immediate return is 

 obtained from the land for a whole season. Another objection 

 offered is that much of the plant-food may be leached out of 

 the soil and carried away in the drainage water, if the lands 

 have a steep slope and the rains are heavy. Experiments 

 conducted by Mr. W. A. McLaren at Vereeniging, Transvaal, 

 have shown, however, that summer fallowing was followed 

 by an increase of 11 muids (2,200 lbs.) per acre in the maize 

 yield, without the use of fertilizers. At one of the American 

 State Experiment Stations the yield of wheat from a field 

 cropped only in alternate years, during a period of ten years, 

 was greater than from a field cropped every year during the 

 same period, thus five crops gave a heavier yield than ten. 

 Somewhat similar results were recorded by Lawes and Gilbert 

 at Rothamstead, England. 



If the total yield obtained by cropping in alternate years 



