A large, evergreen tree, 12-15 m (40-50 ft.) tall, it has dense pinnate leaves. Clusters of small white flowers appear in spring to be followed by long greenly-yellow fruits each containing a seed. The wood secretes resin, and margosa or neem oil is made from the seeds.
History and traditions
A common tree of southern Asia, it has played an important role in Ayurvedic medicine, and in agriculture and domestic life as an insect repellent since earliest times. The first part of the botanical name is from a Persian word meaning “noble tree”, reflecting its many useful properties, which remain valid to this day. The Neem Foundation, Bombay, dedicated to its study, was established in 1993 and the tree’s potential as a source of a low-cost, environmentally-friendly pesticide for field crops in developing countries is currently being investigated.
Growth
It will not grow in temperatures below 15°C (59°F). It requires sun and tolerates poor, dry soil.
Uses
Medicinal
Neem has anti-inflammatory and insecticidal properties, reduces fever, and acts as a tonic and detoxicant, increasing vitality. It is used in the treatment of malaria and has been found to have some effect against leprosy. Also used externally for skin disorders and irritations, especially boils and ulcers, and in eye and ear complaints. Twigs can be used to clean teeth, prevent breath odour and protect from infection.
Cosmetic
Reputed to prevent hair loss if a decoction of the leaves is applied as a rinse. The oil is used in hair and skin lotions, toothpaste and soap.
General
Makes an effective mosquito and insect repellent, and insecticide for crops. In its countries of origin the dried leaves are used to protect stored clothes or books from insect damage. Although it has been found to be safe and efficient as a sheep dip, this use has not been developed commercially.
