136 FIELD CROP PRODUCTION 



28 mules or a tractor engine being required. It can be 

 used with profit only when extensive acreages are grown 

 in one field. 



124. Storing of wheat. Thrashed grain may be stored 

 safely in any tight bin or granary. Owing to the dry 

 weather of the Pacific Coast States, thrashed grain is 

 frequently allowed to remain in the field until marketed, 

 or even after marketing it may be stored by piling the 



FIG. 45. Thrashing wheat in the Northwest. 



bags in great heaps out in the open. The moisture con- 

 tent of thrashed grains varies with the humidity of the 

 atmosphere. When wheat is shipped from a dry to humid 

 climate, frequently the increase in weight is enough to 

 pay for the transportation. 



IMPROVEMENT OF WHEAT 



125. Opportunities for improvement. With the acre 

 yield of wheat less than 15 bushels in great agricultural 

 countries like the United States and Canada, it would 

 seem that there is an abundance of opportunity for in- 



