22 CIRCULAR NO. 115, BUREAU OF PLANT INDUSTRY. 
NORTHWARD EXTENSION OF LONG-STAPLE COTTON. 
The Norfolk experiment is significant, not only as an example of 
the beneficial effects of controlling the formation of the vegetative 
branches, but also as an indication of the possibility of extending the 
cultivation of the Durango cotton and perhaps of other long-stapie 
varieties along the northern border of the cotton belt and even beyond 
the present limits of cotton cultivation. At any such rate of pro- 
duction as that shown at Norfolk, the Durango cotton is a very 
profitable crop, for the fiber attains a length of 14 inches under 
favorable conditions, is of high quahty, and sells, when properly 
handled, at a premium of 5 cents or more a pound above correspond- 
ing grades of short-staple cotton. Such a premium means an addition 
of about $25 per bale to the farmer’s profits. Though it has long 
been known that fiber of good quality could be produced in the 
northern rim of the cotton belt, the late-maturing habits of the older 
long-staple varieties rendered the crop small and precarious. But 
with the new varieties and new cultural methods that have now 
become available the outlook is entirely changed. 
CONCLUSIONS. 
The new system of cotton culture is based on the application of a 
principle not hitherto recognized in cultural experiments—the con- 
trol of the vegetative branches by improved methods of thinning. 
The formation of vegetative branches can be controlled by leaving the 
plants closer together during the early stages, until the stalks have 
grown beyond the stage where vegetative branches are produced. 
The essential feature of the new system is later or more gradual 
thinning. This makes it possible to leave more plants in the rows 
than is now customary, and yet injurious crowding is avoided 
through suppression of the vegetative branches. 
The control or suppressicn of the vegetative branches also permits 
an earlier development of fruiting branches and leads to the produc- 
tion of an earlier crop. In regions where the pericd of crop produc- 
tion is limited, either by short seasons or by the presence of the boll 
weevil, increased earliness is a means of securing larger yields. 
[Cir. 115] 
