190 THE CHIEF SOUTHERN AGRICULTURAL CROPS 



be a distinct species. They are about equal as fiber 

 producers, but the Yucatan variety lasts longer be- 

 fore flowering, so that fields do not require replant- 

 ing as often. These plants, like all the other Agaves, 

 or so-called century plants, produce only a rosette of 

 stiff, fleshy leaves for a number of years, the number 

 differing with the species, when a gigantic flower 

 stalk appears, and after flowering the plant dies. 

 Other fiber-yielding species of the same group occur 

 in Mexico, also in Cuba, and other of the West In- 

 dies, but none have so far proved of much commer- 

 cial importance. 



But little attention has been paid to the diseases 

 and insects of sisal. Plants are sometimes infested 

 by mealy bugs, and they are also attacked by a 

 fungus which causes an anthracnose, or pitlike 

 spotting of the leaves; no remedies are used for 

 either trouble. 



Tobacco {Nicotiana Tahacuni) 



Tobacco is a plant of great importance to Southern 

 agriculture. While grown under a rather wide range 

 of conditions, its cultivation is usually restricted to 

 certain well-defined areas, where the farmers have 

 become accustomed to the methods of handling this 

 exacting and sensitive crop. 



The different classes of tobacco have different re- 

 quirements as to soil and climate. The heavy plug to- 

 baccoes require a rich, rather heavy clay loam ; while 

 to produce the best types of cigar tobacco, a light, 

 sandy soil is necessary. Bright plug and smoking 



