4 BULLETIN 1011, U. S. DEPARTMENT OF AGRICULTURE. 



In 1917 the experiments were conducted at the United States Ex- 

 periment Farm, San Antonio, Tex., the Giles Farm, Waco, Tex., and 

 the Yarrow Plant-Introduction Field Station, Rockville, Md. ; in 1918 

 at the Rockville station: in 1919 at the Rockville station and at the 

 Arlington Experimental Farm, Rosslyn, Va., near Washington, D. C. 



PREPARATION OF THE SEEDS. 



The preparation of the seeds used in the experiments conducted 

 during the period from 1917 to 1919 was as follows: Four lots of seed 

 were composited from four ears of United States Selection No. 119, 

 a white dent variety, in such a manner that each ear was represented 

 in the same proportions in each of the four lots. One lot received no 

 injuries and was the "entire seed" or "check" (PI. I, fig. 1), of the 

 experiments. In the second lot (PI. I, fig. 2), the seed coats, or hulls, 

 were entirely removed. In the third lot (PI. I, fig. 3), the crowns 

 were cut off and as much of the soft starch removed as could be done 

 without breaking the kernels. The hulls were not removed except 

 the portion cut away with the crown. In the fourth lot (PI. I, fig. 4), 

 the entire endosperm was removed, leaving the isolated germ. The 

 germ in the sense used in this article is the combined scutellum and 

 embryo. The same methods of preparing the seed were followed each 

 year. The different classes, for convenience in discussion, are termed 

 check, dehulled, starchless, and germs. 



PLAN OF THE EXPERIMENTS. 



The plan of planting was the same each year and at all places. 

 The following list shows the arrangement of the rows and the kind 

 of seed planted in each row: 



Row No. 1. Guard, United States Selection No. 119. 



2. Entire seed. 



3. Hulls removed, dehulled. 



4. Hulls removed, dehulled. 



5. Entire seed, check. 



6. Soft starch removed, starchless. 



7. Soft starch removed, starchless. 



8. Entire seed, check. 



9. Endosperm removed, germs. 



10. Endosperm removed, germs. 



11. Entire seed, check. 



12. Guard, United States Selection No. 119. 



The distance between rows and between hills in the row was 3.3 

 feet except at San Antonio, where the distance was 4 feet and 3.5 

 feet, respectively. The number of hills in each row varied from 22 to 

 25. The rate of seeding was four kernels to the hill, and the stands 

 were thinned to two plants. No fertilizers were used. 



