12 BULLETIN 1153, U. S. DEPARTMENT OF AGRICULTURE. 



of the wider spacing and larger size of the individual plants, but in 

 the opposite direction, of spacing closer in the rows to restrict the ] 

 size of the plants and bring them to maturity earlier in the season, i 

 Restricting the growth of the plants does not mean that they are to 

 be checked or stunted, for time is lost in starting again when growth 

 has been stopped by any serious setback to the crop. Large plants 

 are more exposed to serious checking by drought or other unfavorable 

 conditions than plants of the medium or small size that are produced 

 by closer spacing. 



Large plants require more time to set a crop and may fail to open 

 their bolls before frost, while the smaller plants in the same fields 

 may have opened all their bolls. The earlier opening of the bolls 

 of small plants is a fact that most farmers know or can observe 

 readily for themselves, and this is a very important fact in relation 

 to the spacing problem. The damage that the frost does to the bolls 

 of large plants is usually avoidable through cultural control of the 

 size of the plants. Though many special features and local appli- 

 cations of the closer spacing methods remain to be worked out, the 

 need of restricting the growth of the plants as a means of securing 

 earlier and larger crops is widely recognized and frequently dis- 

 cussed in agricultural newspapers. 



Since the weevils do not breed until there are flower buds to feed 

 upon, the object of cultural expedients is to set a crop as quickly 

 as possible after the flower buds begin to form but before the weevils- 

 have increased to such numbers that all of the buds are infested. 

 Thus, earliness should be measured by the period between the forma- 

 tion of flower buds and the setting of a crop rather than by the 

 date of the first flower or the total number produced. Relatively 

 little damage usually is done to earl}- bolls, as the weevils prefer 

 to feed and lay their eggs in the floral buds, being by habit and 

 preference bud weevils instead of boll weevils. The advantage of 

 producing many flowers and setting many bolls in a short space 

 of time does not lie with the large, widely spaced plants, but with 

 the small or medium-sized plants, when adjacent rows of the differ- 

 ent spacings are compared. The large plants may grow much 

 faster, but do not on that account set a crop more rapidly or safely. 



Even though small plants, standing close together, may not begin 

 to flower quite as early as larger and more widely spaced plants, a 

 distinct advantage of practical earliness may be shown by small 

 plants in being able to set larger numbers of bolls in shorter periods 

 of time and thus make full use of any favorable conditions that may 

 occur. The general rule is that large plants require more time, both 

 for setting and for maturing the crop. Thus, at San Antonio, 

 Tex., in the season of 1914. when the fruiting period was very short, 

 the yields of Acala cotton spaced to 4 inches in the row more than 

 doubled the yields of rows with 2-foot spacing 'that produced large, 

 spreading plants. 



In comparisons of G-inch and 12-inch spacings of Lone Star cotton 

 at San Antonio in 1921, with rows 4 feet apart, even the 6-inch 

 plants grew rather large and produced enough vegetative branches 

 to close the lanes and shade the ground between the rows. The 

 yields of the 6-inch and the 12-inch spacings. compared in alternate 

 4-row blocks, were nearly equal, although the 6-inch rows were 



