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www.growables.org/information/Tr...eaAmericana.htm

Growables

The large, lustrous dark green evergreen leaves and low-branching, open canopy of Avocado makes it a wonderful shade tree but it is most often grown for the abundant production of its well-known, delicious, buttery fruits. 1

Races and cultivars
The avocados cultivated in the United States are classified horticulturally in three races: the West Indian, the Guatemalan, and the Mexican. The West Indian and Guatemalan races, so far as can be judged at present, are two expressions of one botanical species, Persea americana, while the Mexican race represents a distinct species, P. drymifolia. Horticultural varieties of the avocado, when propagated from seed, do not reproduce the parent fruit in every detail. 3