The cashew tree grows in tropical areas with an annual rainfall ranging from 400 to 4,000 mm, and it grows from sea level to an altitude of 1,000 m. The Cashew is cultivate primarily in India, Vietnam, Côte d'Ivoire, Guinea-Bissau, Tanzania, Benin, Brazil and other countries in East and West Central Africa and South East Asia. Plantings have also been established in South Africa and Australia.

Cashew (Anacardium occidentale L.) belongs to the Anacardiaceae family, which includes about 60 genera and 400 species, among mango (Mangifera indica L.) and pistachio (Pistacia vera L.) are also included. Cashew trees are evergreen and can grow rapidly up to 20 m, but usually reach 8-12 m height. Anacardium occidentale L. is an andromonoeic species, with male and hermaphrodite flowers on the same plant and in the same panicle.

The cashew tree is evergreen. It grows up to 12 metres high and has a spread of 25 metres. Its extensive root system allows it to tolerate a wide range of moisture levels and soil types, although, commercial production is advisable only in well-drained, sandy loam or red soils. Annual rainfall needs to be at least 889mm (35 inches) and not more than 3048mm (120 inches). Cashew trees are most frequently found in coastal areas.

The main commercial product of the cashew tree is the nut. In the main producing areas of East Africa and India, 95% or more of the apple crop is not eaten, as the taste is not popular. However, in some parts of South America and West Africa, local inhabitants regard the apple, rather than the nut kernel, as a delicacy. In Brazil, the apple is used to manufacture jams, and soft and alcoholic drinks. In Goa, in India, it is used to distil a cashew liquor called “feni”.

The cashew fruit (figures 1 and 2) is unusual in comparison with other tree nuts since the nut is outside the fruit. The cashew apple is an edible false fruit, attached to the externally born nut by a stem. In its raw state, the shell of the nut is leathery, not brittle. It contains the thick vesicant oil, CNSL, within a sponge-like interior. A thin testa skin surrounds the kernel and keeps it separated from the inside of the shell. The primary products of cashew nuts are the kernels which have value as confectionery nuts. Cashew nut shell liquid (CNSL) is an important industrial raw material for resin manufacture and the shells can be burned to provide heat for the decorticating operation.