THE AVOCADO 11 



tree and has suggested cultural practices and methods which 

 are producing satisfactory results. In addition, problems of 

 budding and grafting have been mastered, and these means of 

 propagation are practiced successfully by nurserymen, with the 

 result that trees of the best varieties are obtainable in quantities 

 which permit of extensive commercial plantings. A large 

 number of varieties is being tested, and experience in handling 

 and marketing the fruit is being gained rapidly. 



BOTANICAL DESCRIPTION 



The genus Persea, to which the avocado belongs, is a member 

 of the laurel family (Lauracese) ; hence it is related to the 

 cinnamon tree, camphor, and sassafras. The avocados cul- 

 tivated in the United States usually have been considered 

 to represent a single species, Persea americana, but careful 

 study shows that they are derived from two species, as 

 follows : 



P. americana, Mill. (P. gratissima, Gaertn.). All of the 

 varieties classified horticulturally as belonging to the West 

 Indian and Guatemalan races are of this species. It is the 

 common avocado of the tropical American lowlands, and the 

 one which has been most widely disseminated throughout the 

 tropics. 



P. drymifolia, Cham. & Schlecht. (P. americana var. drymi- 

 folia, Mez). This includes the small avocados of the Mexican 

 highlands, now grown in California, Chile, and to a very limited 

 extent in southern France, Italy, and Algeria. Horticulturists 

 in the United States use the term "Mexican race" to indicate 

 avocados of this species. 



In addition to these two species, a third is well known in 

 southern Mexico and Guatemala, and has recently been intro- 

 duced into the United States. This is the coyo or chinini, P. 

 Schiedeana, Nees. The yas of Costa Rica (probably P. Pittieri, 



