170 TROPICAL AGRICULTURE 



which develop at the base of the mother plant or grow up from 

 the roots of the old plant at some distance away. The pole 

 plants are the peculiarly modified structures which develop 

 from the flowers on the branched inflorescence of the flower- 

 ing pole. About 3,000 pole plants develop on each pole. 



During the whole life of the sisal plant about 180 leaves are 

 developed and these leaves yield on an average 10 pounds of 

 fiber. The bearing period of sisal is about 5 years and the an- 

 nual acre production is approximately 600 pounds of dry fiber. 



Sisal is extremely drought resistant and will thrive where 

 most cultivated crops would utterly fail. It would withstand 

 absolute droughts of 6 months' or more duration. In fact, the 

 young suckers may be left exposed to the sun on the surface of 

 the soil for a period of 6 months without losing their vitality. 

 On account of the drought-resistant properties of sisal and its 

 general hardy nature, little or no cultivation is absolutely re- 

 quired. In some of the larger tropical plantations the pole 

 plants or suckers are merely set a few inches into the soil by 

 means of a bar or similar instrument and without any previous 

 plowing or preparation of the soil. In this position plants are 

 allowed to grow and produce their crops of leaves without fur- 

 ther attention. It has been found, however, that sisal will 

 come into bearing at least one year sooner if the ground is 

 thoroughly plowed before planting. In Hawaii, it has been 

 found that sisal will grow in highly manganiferous soil where 

 pineapples and most other crops would fail utterly. Sisal 

 thrives fairly well in a great variety of soils., Near Honolulu 

 there is a small plantation in coral limestone and another in 

 manganiferous soil. The sisal appears to thrive equally well 

 in .both these soils. 



Various machines have been used in removing the sisal fiber 

 from the leaves. The one which has given best satisfaction is 

 called a raspador. In this decorticating machine the leaves are 

 grasped by one end, while the pulp from the remainder of the 

 leaf is crushed and carried away by a revolving wheel, after 



