A small deciduous shrub or tree 4 to 8 m tall with dense, round crown. Sometimes it may be prostrate and form impenetrable thickets. Bark is brown and rough. Branches and branchlets are slender, brown or light brownish in colour with prominent corky leaf scars. Leaf shape is highly variable, elliptic or oblong-elliptic or oblong or even sub-ovate, 3 to 12 cm long, 2 to 8 cm wide and opposite in arrangement. Tip of the leaves is also variable, obtuse to short acuminate or ending abruptly in a short sharp point. Leaf margin is smooth, sometimes shallowly notched or coarsely serrated. Inflorescence is terminal, much branched and many flowered. Flowers are small with distinctly toothed calyx, greenish, or pale greenish-white or pale yellowish- white in colour and unpleasantly aromatic. Fruit is a small round drupe, fleshy, surrounded at the base by enlarged calyx and dark blue or black in colour when mature. Stone is hard, normally four chambered and four seeded.
Premna's Behavior & Ecology
It is well adapted to shallow, dry, alkaline coastal soil but better performance is seen in deep soil with high moisture content. It is also capable of growing in rocky areas near the shore. Its tolerance to drought and aerosol salt spray is high and tolerance to soil salinity is moderate. It is not cultivated in the Maldives though it can be propagated by seed and stem cuttings. Seeds can be removed from the fruit by crushing them in water and can be used for direct sowing. Seedling growth is moderate and requires regular watering but intolerant to excess watering. Stem cuttings 1 to 1.5 m height and 6 to 10 cm in diameter can be used for easy establishment.
Premna's Relationship with Humans
In the Maldives, it is considered as ideal firewood and it is a tradition to use branches and twigs of this tree to make ‘first fire’ in new kitchens. It is also grown as shade tree in houses, schools and other public places. Wood is used for handicrafts and to make handles of small tools. Straight long poles, which are light weight and durable, are commonly used as handle of scoops or buckets that are used to draw water from shallow wells. Poles are used to provide support to beetle vein. Leaves are eaten to increase mother’s milk. Leaves and roots are also used in traditional medicine to alleviate rheumatism and neuralgia and weakness of the limbs. It is a strong wind breaker and, hence, can be an important component in multiple coastal bioshield.
Premna serratifolia is a small tree, up to 10 m tall. It mostly grows in moist sandy soil and scrub jungles along seacoasts and mangrove forests. It is also found in the interior, growing in humid forest, at sea level to 2,200 m elevation.
Premna serratifolia is threatened by the several local uses. It is also threatrened by habitat destruction due to illegal forest logging and extension of agricultural land.