COTTON-SPACING EXPERIMENTS 13 
COMPARISON OF 6-INCH AND 12-INCH SPACINGS AND UNTHINNED ROWS 
EXPERIMENT A 
Experiment A isso designated to differentiate it from another test 
in which 6-inch and 12-inch spacings were compared with unthinned _ 
rows. (Tabie 5 and fig. 5.)} 
There was no outstanding difference in yields of the three spacings 
compared. The rows giving highest yields usually occur in the un- 
yee blocks but are often those which adjoin a wider spacing. 
(fig. 5) ; 
In three out of six comparisons between the inside rows of the un- 
thinned blocks with the inside rows of the 12-inch spaced blocks, the | 
unthinned rows gave greater yields. One comparison was a tie and | 
two were in favor of the 12-inch spacing. The mean increase in favor. 
of the unthinned rows is 0.233 + 0.286 pound of seed cotton. Since: the” 
probable error is greater than the difference, the increase is not 
significant. 
In making a similar comparison of six adjoining blocks of 6-inch 
and 12-inch spacing, the 6-inch blocks give higher yields in only three 
cases, but the mean difference, 0.05 + 0.146 was in favor of the 6-inch 
spacing. This difference is less than the probable error and is not 
significant. 
Only four comparisons are possible between the aathideed and the 
6-inch spacing. The unthinned rows gave higher yields i in only two 
of these comparisons, but show a mean increase over the 6-inch spac- 
ing of 0.275+0.202 pound of seed cotton. This difference is only 
1.36 times the probable error and is not significant. Though the 
close-spaced cotton gave a slightly higher total yield in all of the 
comparisons, the increase was too small to be considered significant 
and the aes compared should be regarded as producing equally 
we 
EXPERIMENT B 
Experiment B is also a comparison of ahora rows W vith 6-inch 
and 12-inch spacings. By planting delinted seed at the rate of. about 
40 pounds to the acre an exceptionally thick stand of plants was 
obtained. This heavy planting of seed, which produced a stand of 
plants spaced extremely close, was made for the purpose of studying 
the effect on what would be considered badly over-crowded plants. eptn: 
1In Figures 5 to 18, inclusive, the lower, heavily shaded portions of the columns represent the-first pick - 
ing an the upper OSES the second picking. , 
