May 3i, 1924 Comparison of Pima Cotton with Upland Varieties 
953 
The Pima variety produced higher yields of seed cotton than any of the 
Upland varieties included in the test during the first three years. In 1923 
there was no material difference in the yields of the varieties. The highest 
yield, 2,406 pounds of seed cotton per acre, was produced by Acala, followed 
by Mebane with 2,390 pounds, and by Pima with 2,368 pounds per acre. 
Acala cotton produced somewhat higher yields than Hartsville when late 
plantings of the two varieties were compared in alternate plats. 
By obtaining the weights of three representative samples of 20 bolls each 
from the different varieties it was determined that only 50 bolls of Lone Star 
cotton were required to make a pound of seed cotton, whereas 122 bolls of Pima 
were required. The number of bolls of Hartsville, Durango, Acala, and Mebane 
required to make a pound were 60, 76, 63, and 56, respectively. 
Examinations of representative samples of the several varieties showed a 
range of lint percentages from 25 to 36 in the Upland varieties and from 26 to 28 
in Pima. The lowest percentages were in Hartsville and the highest in Lone 
Star. The lint index or weight of fiber from 100 seeds was lowest in Pima and 
highest in Lone Star. 
The strong central stalks and upright habits of the Pima, Hartsville, Durango, 
and Acala varieties are recognized as advantages in irrigated regions, where 
damage to bolls and difficulties in picking are often caused by the “lodging” or 
prostration of plants of varieties with lower and more spreading habits of growth, 
as Mebane and Lone Star. 
LITERATURE CITED 
(1) Balls, W. L. 
1912. THE COTTON PLANT IN EGYPT, STUDIES IN PHYSIOLOGY AND GENET¬ 
ICS. 202 p., illus. London. 
(2) Ewing, E. C. 
1918. A STUDY OF CERTAIN ENVIRONMENTAL FACTORS AND VARIETAL 
DIFFERENCES INFLUENCING THE FRUITING OF COTTON. Miss. 
Agr. Exp. Sta. Tech. Bui. 8, 93 p. 
(3) King, C. J. 
1922. WATER-STRESS BEHAVIOR OF PIMA COTTON IN ARIZONA. U. S. Dept. 
Agr. Bui. 1018, 24 p., illus. 
(4) Lloyd, F. E. 
1916. THE ABSCISSION OF FLOWER-BUDS AND FRUITS IN GOSSYPIUM, AND 
ITS RELATION TO ENVIRONMENTAL CHANGES. TranS. Roy. SoC. 
Canada (III) 10 (IV): 55-61. 
(5) - 
1920. ENVIRONMENTAL CHANGES AND THEIR EFFECT UPON BOLL-SHED¬ 
DING in cotton. Ann. N. Y. Acad. Sci. 29: 1-131, illus. 
(6) Martin, R. D., Ballard, W. W., and Simpson, D. M. 
1923. growth of fruiting parts in cotton. Jour. Agr. Research 25: 
195-208, illus. 
(7) -and Loomis, H. F. 
1923. summer irrigation of pima cotton. Jour. Agr. Research 23: 
927-946. 
