Avocado ( Persea americana ) is a tree native to Central America and the fruit of that tree, classified in the flowering plant family Lauraceae . The tree grows to 20 m (65 ft), with alternately arranged, evergreen leaves , 12-25 cm long. The flowers are inconspicuous, greenish-yellow, 5-10 mm wide. The pear -shaped fruit is botanically a berry, from 7 to 20 cm long, weighs between 100 to 1000 g, and has a large central seed , 3 to 5 cm in diameter.

An average avocado tree produces about 120 avocados annually. Commercial orchards produce an average of 7 tonnes per hectare each year, with some orchards achieving 20 tonnes per hectare. Biennial bearing can be a problem, with heavy crops in one year being followed by poor yields the next. The fruit is sometimes called an avocado pear or alligator pear , due to its shape and rough green skin. The avocado tree does not tolerate freezing temperatures, and so can be grown only in subtropical and tropical climates.

Source: http://en.wikipedia.org/wiki/Avocado