282 FIELD CROPS FOB THE COTTON-BELT 



little attentipn that has been given to the production of 

 new or improved varieties of oats in the United States, 

 many of our best varieties have been introduced from 

 foreign countries. Relief from this source, however, is 

 quite limited. Future progress must be based largely on 

 the selection and improvement of the varieties that we 

 now have.' The practice of exchanging seed from one 

 locality to another within the United States or even within 

 the cotton-belt is quite common. Experience and ex- 

 periments have shown that httle permanent improvement 

 can be secured by this practice. On the other hand, it 

 usually results in decreased yields. In an experiment 

 conducted at Amarillo, Texas, by the office of Grain In- 

 vestigations, Bureau of Plant Industry, Washington, 

 D. C, "home grown seed of Burt oats yielded practically 

 twice as much as an adjoining plot of the same variety 

 from seed which had been grown in central Kansas for two 

 years, though both lots were grown from the same original 

 stock." 



343. Mechanical selection. — Running seed oats 

 through a good fanning mill so adjusted as to remove the 



'light-shriveled grains as well as weed seeds and dirt is a 

 very commendable practice. While little permanent im- 

 provement can be secured by such treatment, tests have 

 repeatedly shown increased yields due to the removal 

 of the poorly developed seeds that either will not germinate 

 or that produce very weak, improductive plants. 



344. The seed-plot. — The maintenance of a seed- 

 plot is based on the principle of slow and gradual amel- 

 ioration of the crop by propagating each year from mixed 

 seed secured from a number of select plants that conform 

 to the same type. The first year, seed is selected from a 

 sufficient number of plants, which show superior qualities 



