38 



BULLETIN 836, U. S. DEPARTMENT OF AGRICULTURE. 



The annual yields of brush are shown in Table XIV, together 

 with 3-year and 5-year averages, so that comparisons may be made 

 readily between the yields from different rates. These same data 

 are shown again in Table XXI with similar data regarding other 

 methods of spacing, for comparison between methods. Those rates 

 which are comparable for at' least three years are shown in Table 

 XIV. Rates that did not differ more than 1 inch in row space per 

 hill in the different years are treated as one rate of seeding. The 

 same is true of the 6 to 7 inch and the 9 to 10 inch stands. The 11 

 to 14 inch stands are grouped as one rate also, though they cover 

 a larger difference (3 inches) in row space per hill. 



Table XIV. — Annual and average acre yields of Acme broom com in the com- 

 bined rat e-of -seeding and spacing experiments at the Woodward (Okla.) Field 

 Station during periods of varying length in the 5-year period from 191% to 

 1918, inclusive. 



[One plant in each hill; rows spaced 3.5 feet apart.] 





Annual acre yields (pounds). 



Average yields. 



Distance 

 between hills. 



1914 



1915 



1916 



1917 



1918 



3 years, 1916 

 "to 1918. 



5 years, 1914 

 to 1918. 





Good. 



Poor. 



Good. 



Poor. 



Good. 



Poor. 



Good. 



Poor. 



Good. 



Poor. 



Good. 



Poor. 



Good. 



Poor. 



4 to 5 inches... 

 6 to 7 inches... 

 9 to 10 inches.. 

 11 to 14 inches. 



215 

 305 

 250 



2S0 



90 

 60 

 20 

 10 



775 

 685 

 590 

 735 



87 

 110 

 75 

 70 



405 

 531 

 480 

 415 

 295 



65 

 44 

 75 

 90 

 120 



380 

 350 

 290 

 295 

 330 



125 

 90 

 55 

 55 

 65 



180 

 281 

 235 



257 

 288 



31 

 38 

 25 

 43 

 37 



332 

 387 

 335 

 322 

 304 



75 

 57 

 52 

 63 

 74 



391 



430 



• 369 



396 



80 

 68 

 50 

 54 

















The highest annual yield of good brush produced in the 5-year pe- 

 riod was 775 pounds from the 4 to 5 inch rate in 1915, and the lowest 

 annual yield was 180 pounds from this same rate in 1918. Here it is 

 seen that the rate which yields highest in a favorable season yields 

 lowest in an unfavorable one. Therefore, the most profitable rate is 

 one that makes fair to good yields each year and a fair average yield 

 in a series of years. The highest average yield in both the 3-year 

 and the 5-year periods was made by the 6 to 7 inch rate. This rate 

 averaged 387 pounds of good brush in the 3-year period from 1916 

 to 1918, inclusive, or 52 pounds more than its nearest competitor. In 

 the 5-year period, from 1914 to 1918, inclusive, the 6 to 7 inch rate 

 averaged 430 pounds of good brush. The next highest was 396 

 pounds from the 11 to 14 inch rate, or 34 pounds less. 



TWO PLANTS PER HILL, ROWS 3.5 FEET APART. 



Table XV shows the agronomic data from rows spaced 3.5 feet 

 apart with plants grouped two in each hill in the rate-of-seeding and 

 spacing experiments. In this second section of the experiments each 

 hill contains two plants instead of one, and the hills occupy twice the 



