16 



vfew. Ag j n h e methods of harvesting, so in the methods of thrash- 

 ing great changes have taken place. In former times the flail 



37 was used or the grain was trodden out by horses or oxen, and 



38 these methods are still practiced where agriculture is con- 

 ducted on a small scale or in a primitive manner. Generally, 

 however, to-day thrashing machines are operated by horse, 

 steam, gas engine, and electric power. A great improvement 

 in machines also has been made, the largest recent improved 

 outfits under favorable conditions being capable of turning 

 out as many as 2,000 bushels in one day. Formerly from 500 

 to 600 bushels were considered a good day's run. 



STORAGE. 



39 In storing wheat the object should be to keep it dry and to 



40 prevent insect depredations. Stored wheat often changes in 



41 weight as a result mainly of variations in moisture content. In 



42 dry climates slight gains in weight occur during winter storage, 

 and wheat harvested and cured under arid conditions and then 

 transported to humid climates will at times show marked gains 

 in weight during transit and storage. In humid regions wheat 

 has a tendency to lose in weight after thrashing, but in arid 

 and semiarid climates this tendency is not so apparent. 



THE USES OF WHEAT. 



The principal value of wheat lies in its use for the manufac- 

 ture of flour for bread and pastry. The flour of durum wheat, 

 generally richer in gluten than the flour of common wheats, is 

 used for macaroni, spaghetti, and other pastes. The by- 

 products of the mill are used for feedirg purposes and the chaff 

 and straw for feed and bedding. Winter wheat also is pas- 

 tured in southern sections, where it makes a comparatively 

 large growth in the fall or winter, but caution should be used 

 in following this practice. 



DISEASES AND INSECT ENEMIES. 



43 The most common diseases of wheat are the rusts and smuts, 



44 and the most common insect enemies the chinch bug and the 

 Hessian fly. The cojnmon rusts are the orange-leaf rust (Pue- 

 cinia rubigo-vera) and the black rust (P. graminis). The most 

 injurious smut is the stinking smut or bunt (Tilletia fatens] . 



45 The loose smut ( Ustilago tritici) is much less injurious than the 

 stinking smut. Injuries to the wheat crop from the chinch 

 bug and the Hessian fly are often very extensive. For the 

 prevention of stinking smut seed wheat is either soaked in hot 

 water (132 to 133 F.) for 10 to 15 minutes, immersed in a 



