188 THE CHIEF SOUTHERN AGRICULTURAL CROPS 



air, thus securing the prompt drying of the bolls, 

 when wet from rain or dew. 



Another serious trouble of the cotton planter is 

 the shedding of the young bolls, thus causing the 

 plant to fail to set a sufficient crop. This shedding 

 is not due to insects or fungi, but seems to be caused 

 by some derangement of nutrition. It may occur if 

 the weather is either too wet or too dry; but is 

 more frequently caused by a period of sharp drought 

 following abundant rains that have caused the plants 

 to take on a rapid growth. No remedy is known 

 except to give such cultivation as will avoid, so far 

 as is possible, sudden checks in the development of 

 the plants. 



Sisal (^Agave sps.^ 



This plant furnishes a strong, coarse fiber that is 

 largely used in the manufacture of rope, binder twine, 

 and other cordage. For these purposes it is excelled 

 in importance only by the Manila hemp, which is 

 produced by a species of banana, grown in the Phil- 

 ippine Islands. Sisal, or heniquen, as it is often called, 

 is grown very extensively on the Yucatan peninsula 

 in Mexico, and is also planted to some extent in the 

 Bahamas and at certain points in northern Cuba. 

 To succeed best, the plant requires a dry, rocky, lime- 

 stone soil. It does not withstand frost, so can be 

 grown only in tropical regions. While the plant 

 grows well on deeper, richer land, it is too pulpy in 

 such situations and yields a smaller percentage of 

 fiber. Commercial plantings are entirely confined to 



