i”) 
COTTON-SPACING EXPERIMENTS 4G 
Close spacing reduces the size of the plant and allows a greater num- 
ber of stalks to be left in the row without injurious crowding. The 
fruiting branches on closely spaced plants are short, and the crop is 
produced on the first few nodes of the branches. Since the cotton 
plant fruits more rapidly vertically along the axis of the plant than 
horizontally along the fruiting branches, the setting of early bolls is 
promoted by leaving the plants close together. 
Percentage of lint and length of lint are apparently not affected by 
close spacing, but the size of the bolls 1s slightly reduced. 
The yields from the unthinned rows, where the plants averaged 
from 2 to 4 inches apart, and from the 6-inch spacings were usually 
greater than from the rows where the plants were spaced 12 inches 
apart. In a few cases the wider spacings gave a higher total yield, 
but the increase was significant in only one experiment. 
The yield of the 6-inch spacing is generally higher than that of the 
12-inch spacing. The 6-inch spacing tends to approximate the yield 
of the unthinned rows and is sometimes greater. This indicates that 
better yields are obtained on the black land when the plants are 
spaced less than 12 inches apart in the row. 
Several stalks to the hill produced more cotton than one stalk to 
the hill where the hills were more than 12 inches apart. 
Chopped rows compared with unthinned rows indicate that the 
yield is more likely to be reduced than increased by chopping. 
There appear to be chances for greater increase in yields from 
closely spaced plants where grown on light soils, than on heavy soils, 
as the experiments on fine sandy loam showed more outstanding dif- 
ferences in favor of the unthinned rows. 
Closely spaced plants produce few vegetative branches, so that the 
lanes between the rows are left open and exposed to direct sunlight 
during the summer. The heat of the sun in the open row lane rap- 
idly dries out the squares containing the boll-weevil larve and mate- 
rially reduces their number. By leaving the plants closely spaced 
in the rows, a practical and economical contribution toward weevil 
control is put into operation. 
LITERATURE CITED 
(1) Carpon, P. V. : 
1918. EXPERIMENTS WITH SINGLE-STALK COTTON CULTURE IN LOUISIANA, 
ARKANSAS, AND NORTH CAROLINA. U.S. Dept. Agr. Bul. 526, 31 pp. 
Qj) Coox, 0: F: 
1913. A NEW SYSTEM OF COTTON CULTURE. U.S. Dept. Agr., Bur. Plant 
Indus. Cire. 115: 15-22. 
(3) ——— : 
1913. LEAF-CUT, OR TOMOSIS, A DISORDER OF COTTON SEEDLINGS. U.S. Dept. 
, Agr., Bur. Plant Indus. Circe. 120: 29-34, illus. 
oh) ees Ro 
1914. A NEW SYSTEM OF COTTON CULTURE AND ITS APPLICATION. U.S. 
Dept. Agr., Farmers’ Bul. 601, 12 pp., illus. 
CS) ieee ce 
1920. cOTTON IMPROVEMENT UNDER WEEVIL CONDITIONS. U.S. Dept. Agr., 
Farmers’ Bul. 501, 22 pp. (Revised ed.) 
(6) Hunter, W. D., and Pierce, W. D. 
1912. THE MEXICAN COTTON-BOLL WEEVIL: A SUMMARY OF THE INVESTIG4- 
TION OF THIS INSECT UP TO DECEMBER 31, 1911. U.S. Dept. Agr., 
Bur. Ent. Bul. 114, 188 pp., illus. (U.S. Congress, 62d, 2d sess., 
Senate Doc. 305.) 
