Common Name: Bead Tree

General Information

Melia azederach is a fast-growing, deciduous tree that can reach a height of around 45 metres in closed, moist forests, though it is much smaller in the cooler and drier regions in which it is sometimes grown and where is much more likely to be just 10 - 15 metres tall. The straight, cylindrical bole can be free of branches for up to 20 metres, with no buttresses[]. The tree is generally deciduous, but some forms in the humid tropics are evergreen[].
A very important tree for local people, providing a wide range of medicinal applications; an insecticide and repellent; a useful timber and many other commodities. It is often cultivated in many parts of the tropics for these many useful qualities[, ]. It is planted for re-reforestation in its native areas, where it is a fast growing though short-lived species[, ]. It is often planted as a street tree and ornamental, though it has the disadvantage of dropping a lot of leaf-litter[].
The tree can become invasive in lowland subtropical regions[].

Known Hazards

The fruit is highly toxic to warm-blooded animals[]. Ripe fruits are more toxic than green ones[]. As little as six fruits have caused nausea, spasms and fatalities in children[, ].
All parts of the plant contain toxins that can cause gastric tract irritation and degeneration of the liver and kidneys[].

Botanical References

, ,

Range

E. Asia - central and southern China, India, Sri Lanka, Nepal, Bhutan, Thailand, Laos, Vietnam, Indonesia, Philippiines, eastern Australia

Habitat

Moist sunny locations[]; at elevations up to 2,700 metres in the Himalayas[]. Seasonal forest, including bamboo thickets[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	9.00 m
Growth Rate	Fast
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Melia azadarach is a tree of the subtropical climatic zone, though it is a highly adaptable plant that can tolerate a wide range of conditions from warm temperate with some frost, right through to the humid tropics[]. It is grown at elevations up to 1,800 metres in the tropics[]. It can tolerate a mean maximum temperature in the hottest month of 39°c, with temperatures sometimes falling below freezing for short periods in the cool season[]. In general, trees will be killed by temperatures falling lower than about -5°c[]. It can succeed with an annual rainfall as low as 600mm, competing best in areas that receive less than 900mm[, ].
Prefers a well-drained soil in a sunny or partially shaded position[]. Succeeds in most well-drained soils and in hot dry conditions[]. Likes sandy soils[]. Tolerant of quite poor growing conditions, including shallow soils, saline and strongly alkaline soils, poor, marginal, sloping, and stony land, even in crevices in sheer rock[]. It does not like very acid soils[]. Grows well in mild coastal areas[]. Established plants are very drought tolerant[, ].
Trees can commence flowering when only 5 - 6 years old from seed. In the warmer, non-seasonal areas it can flower and fruit all year round[].
Trees are fast-growing, but can be quite short-lived, often dying by the time they are 20 years old[].
The flowers are produced on the current years wood and have a delicate sweet perfume[, ]. The trees do not normally require pruning[].
The seeds have a strong scent of musk and the wood is also musk-scented[].
Trees are very susceptible to forest fire, though they sprout back readily from the roots[].
Plants do not coppice well from large stumps, but excellent coppice is obtained from trees up to a girth of 0.9 m. The tree resprouts after cutting and regrows after pollarding, making it suitable for pole production[].
Plants in this genus are notably resistant to honey fungus[].

Edible Uses

Leaves - cooked[, ]. A bitter flavour, they are used as a pot-herb, in curries, soups etc[].

Fruit[]. A sweetish flavour, it is eaten by children though some people believe it to be poisonous[]. The fruit is between 1 and 5cm in diameter[] and contains a single seed[].

Both the above reports, of edible leaves and fruits, should be treated with some caution. The fruit is poisonous according to one report where it says that the ripe fruit is more poisonous than the green fruit and that they have sometimes caused human fatalities[].

A cooling drink is made from the sap[] - it is actually a gum[]. This gum is tasteless, clear to dark amber and of good solubility[]. The sap is obtained from incisions that are made near the base of the trunk in the spring[].

Medicinal

An aqueous extract reduces the intensity of asthmatic attacks[]. (This report does not specify the part of the plant that is used[].)

The leaf juice is anthelmintic, antilithic, diuretic and emmenagogue[, ]. A decoction is astringent and stomachic[]. A decoction is used to treat diarrhoea[].
The leaves are used externally to treat skin conditions such as scabies and itch[]. A decoction is used as a gargle to treat tooth problems and strengthen the gums[].
The leaves are harvested during the growing season and can be used fresh or dried[].

The flowers and leaves are applied as a poultice in the treatment of neuralgia and nervous headache[, ].

The stem bark is anthelmintic, astringent and bitter tonic[, , ]. It is used as a tonic in India[]. It can be harvested at any time of the year and is used fresh or dried[].

The root bark is emetic, emmenagogue, purgative and vermifuge[, , ]. It is highly effective against ringworm and other parasitic skin diseases[]. It can be harvested at any time of the year and is used fresh or dried[].

The fruit is antiseptic and febrifuge[]. The pulp is used as a vermifuge[]. The fruit is harvested in the autumn when it is fully ripe and can be used fresh or dried[].

The seed is antirheumatic[, ]. It is used externally.

A gum that exudes from the tree is considered by some to have aphrodisiac properties[].

This plant should be used with caution, preferably under the supervision of a qualified practitioner[]. Excess causes diarrhoea, vomiting and symptoms of narcotic poisoning[].

Agroforestry Uses:

The tree is planted as a pioneer species in northern Thailand in reforestation projects to restore native woodland - it is planted in degraded woodland and open areas in a mix with various other species that all have the ability to grow fast; produce dense, weed-suppressing crowns; and attract seed-dispersing wildlife, particularly birds and bats[].
It is grown as a shade tree in coffee and abaca (Musa textilis) plantations[].

Other Uses

The seed contains up to 40% of a drying oil[]. It is used for lighting, varnish etc[, ]. An oil suitable for illumination has been extracted experimentally from the berries[].

The musk-scented seeds are used as beads in rosaries[, , , , ].

A red dye is obtained from the bark[].

A fibre obtained from the bark is used to make rope[].

The fruits are a source of a flea powder and an insecticide[, ]. The whole fruit is ground up and used[]. The fruit pulp is also used as an insect repellent[].
Aqueous and alcoholic extracts of the leaves and seed reportedly control many insect, mite and nematode pests. However, because they contain toxic components, care is needed in their use[].

The leaves repel mosquitoes and other insects[, , ].

Because it is fast-growing, it is often used as a fuel[, ]. It has a calorific value is 5100 kcal/kg[].

A handsomely marked wood, the heartwood is red to reddish-brown; it is clearly demarcated from the whitish-yellow sapwood. The texture is coarse; the grain is straight; lustre is bright; there is a musk-like aroma. The wood is tough, moderately heavy, somewhat brittle, somewhat durable. It is easy to work; takes an excellent polish. It is used for making furniture, packing cases, construction, decorative veneer etc[, , , , , ].
The wood (the 'white cedar' of commerce), which resembles mahogany, is used to manufacture agricultural implements, furniture, plywood, boxes, poles, tool handles; it is used in cabinet making and in construction because of its resistance to termites[].

Propagation

Seed - sow late winter in a greenhouse. The seed is best sown as soon as it is ripe in the autumn[, ]. The seed usually germinates well. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts[].
Root cuttings[].