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BULLETIN 829, U. S. DEPARTMENT OE AGRICULTURE. 



Mississippi offer no difficulty at all. They can be destroyed with 

 practically no loss to the owners, and the assurance of healthy crops 

 in the future more than offsets the inconvenience of growing some 

 other crop on the land now occupied by infected cane. The success 

 of the measure in Florida is made possible by the present organization 

 of the State plant board, which has already met the test of success- 

 fully handling more serious problems. 



ELIMINATION BY PLANTING IMMUNE VARIETIES. 



Success of the control measures suggested up to the present depends 

 entirely upon the whole-hearted cooperation of all cane growers. 



Fig. 4. — Map of Florida, showing the location of diseased areas of sugar cane in that State. 



There yet remains a method, applicable only to certain regions, by 

 which a planter can make himself wholly independent of any default 

 on the part of his neighbors. A few varieties of sugar cane have been 

 discovered that are absolutely immune to mosaic under all condi- 

 tions. Most of them are of the type referred to as Japanese cane. 

 Their origin is obscure. They have certain characteristics in com- 

 mon. All are tall growing with slender stalks. They stool abund- 

 antly, ratoon well, and produce an enormous tonnage. The sucrose 

 content is not so high as in some of the broad-leaved canes, but in 

 sugar per acre they take first rank with the best existing varieties. 

 The Kavangire, Zwinga, Uba, Cayana 10, and numerous others 

 imported by the office of Foreign Seed and Plant Introduction are 



