180 TROPICAL AGRICULTURE 



fiber used in mats, hammocks, bowstrings, twine, and for vari- 

 ous other purposes. The plants are easily propagated by seed, 

 root division, or suckers. They require little care or cultiva- 

 tion, spread readily by root suckers, and grow wild over large 

 areas. Plantings rarely have to be renewed. Bowstring hemp 

 yields its first crop at about 3 years of age. As a rule, 50 

 pounds of fiber may be expected per ton of leaves. The fiber 

 may be removed by hand machines, or by a sisal decorticator. 

 For this purpose the sisal machine merely requires special ad- 

 justment. In Porto Rico the bowstring hemp is quite an im- 

 portant plant for local uses. A species of bowstring hemp (S. 

 longfflora), quite widely distributed in tropical America, is 

 grown in Florida, especially on the Keys. This species pro- 

 duces fiber ranging from 2 l / 2 to 7 feet in length and yields 

 about 40 pounds of fiber to a ton of leaves. It was introduced 

 into Florida about 1890, but has never become a commercial 

 crop. 



HIBISCUS FIBERS 



Nearly all species of Hibiscus, both ornamental and commer- 

 cial, as well as most species of the whole mallow family, pro- 

 duce a strong and serviceable bast fiber in the bark. Only a 

 few species of Hibiscus, however, have been used for the com- 

 mercial production of fiber. The musk mallow (H. abilmos- 

 chus) has been the subject of experiment in India with refer- 

 ence to the value of its fiber. In these experiments 800 pounds 

 of fiber per acre were obtained. The fiber was found to have 

 no advantage over jute. The Deccan hemp (H. cannabinus), 

 a native of the East Indies, is perhaps the most valuable mem- 

 ber of the genus as a fiber plant. The length of the fiber of 

 Deccan hemp is 5 to 10 feet. The fiber is inferior to true hemp 

 and jute, but is used in India for various agricultural purposes. 

 The stems of the plant are cut, bundled, and retted in water for 

 about a week. The cultivation of the Deccan hemp is much like 

 that of true hemp. The time from seed to harvest is about 3 



