BUREAU OF PLANT INDUSTRY. 273 



the juvenile leaf-curl proves to be quite distinct and does not seem to 

 be due either to insects or to fungous parasites. Experiments are 

 being made to determine methods of avoiding these malformations 

 and of reducing the losses they occasion. 



Control or branching habits of cotton. — It has been found that 

 under conditions of luxuriant growth the cotton plant develops vega- 

 tative branches at the expense of fruiting branches, resulting in a 

 hiter and smaller crop. Experiments are being made to test the 

 possibility of avoiding these difficulties by the restriction of the 

 growth of the plants in the early stages and by the selection of 

 strains with less tendency to the production of vegetative branches. 



Improved methods of culture for irrigated districts. — In view of 

 the probability that cotton will become one of the chief crops in the 

 irrigated districts of the Southwestern States where the danger of 

 weevil injury is less serious than in the more humid eastern districts, 

 attention is being given to the special culture factors of the south- 

 western region. It has become apparent that much injury has been 

 done by the excessive use of water, especially in the earlier part of 

 the growing season, the ability of the cotton plant to resist drought 

 being generally underestimated. In localities where the natural 

 rainfall assisted by dry-farming methods provides moisture for the 

 germination of the seed, it is better to use irrigation only to protect 

 the maturing crop against injury by too severe drought. 



Hindi cotton in Egypt. — A report on Hindi cotton in Egypt, 

 based on a study of the Egyptian cotton industry in the season of 

 1910, shows the extent of the injury inflicted by the Hindi contamin- 

 ation of the Egyptian type of cotton. From countings of the num- 

 bers of Hindi individuals and hybrids in many cotton fields in 

 different localities in Egypt it appears that the annual loss from this 

 cause amounts to several millions of dollars. 



Precocity of the Hindi cotton. — Seedlings of the inferior Hindi 

 type of cotton have been found to germinate more promptly in dry 

 soil and usually outgrow genuine Egyptian seedlings in the same 

 hills. The precocity of the Hindi seedlings explains why the Hindi 

 contamination of the Eg^'ptian cotton has continued to increase in 

 Egypt in spite of the attempt to remove it by seed selection. The 

 native Egyptian cultivators are likely to spare the largest plant in 

 the hill at the time of thinning. More careful methods of selection 

 may be expected to effect a complete exclusion of the Hindi con- 

 tamination from the Egj^ptian cotton that is being grown in the 

 United States. 



Characters of cotton seedlings. — Characters of the seedlings of 

 numerous varieties of Egyptian and Upland cotton have been com- 

 pared with a view to the development of methods for detecting un- 

 desirable variations in the early stages of growth. It has been found 

 that the Hindi variations of Egj'ptian cotton can be recognized imme- 

 diately after germination by differences of the cotyledons or seed 

 leaves. 



Commercial value of corx)R characters in Egyptian cotton. — 

 The popularity of the brown varieties in Egypt may be explained 



23165'— AUR 1911 18 



