Dysoxylum malabaricum


Dysoxylum malabaricum, or white cedar, is a species of tree endemic to the Western Ghats, India. The species is considered Endangered under the IUCN Red List of Threatened Species.

Description

These are tall canopy trees with a straight bole, growing to a height of about. The bark, about thick, is greyish brown and covered densely with large, corky lenticels. The bark exfoliates in large rectangular scales. When the bark is cut, the blaze appears yellow and white. The young branchlets are angular and minutely hairy. The compound leaves are paripinnate, up to long, arranged alternate, spiral, and clustered at twig ends. The petiole is pulvinate. The rachis is angular, long. The leaves have 4-6 pairs of leaflets with petiolules about long. The leaflets are alternate or subopposite, about in length by wide. Leaflets are coriaceous, elliptic-lanceolate in shape and have an acuminate apex, asymmetric base, and an entire margin. The midrib is raised above the dorsal surface of the leaf. Leaflets have 12-20 pairs of prominent secondary nerves, with hairy domatia in the axils of the secondary nerves. Tertiary nerves are obscurely visible and reticulo-percurrent. Prominent inter-secondary veins are seen between secondary nerves.
The inflorescence is a panicled raceme, shorter than leaves. The bisexual flowers are greenish yellow in colour and fragrant, about long. They have a deeply 4-lobed calyx, 4 petals, 8 anthers, and a superior ovary, densely hairy, 4-celled, and with 2 ovules in each cell. The fruit is a capsule, about long, bright yellow, with 4 longitudinal furrows. Each fruit has 3-4 seeds, reddish-brown in colour and bluntly triangular in cross section.

Range

It is found in the mountains of the central and southern Western Ghats, between elevation.

Habitat

Occurs in evergreen and semi-evergreen forests.

Ecology

A rare tree found in low and mid-elevation tropical wet evergreen forests of the Western Ghats. The fruits of this tree were dispersed by wood pigeons and Malabar grey hornbills. A study found that the hornbills ability to disperse the seeds of this plant to long distance is supposedly helping maintain the genetic diversity of this tree species.

Etymology

The etymology of Dysoxylum derives from the Greek word 'Dys' meaning "bad", referring to "ill-smelling", and 'Xylon' meaning "wood". The specific epithet 'malabaricum' refers to the Malabar region of south-western India. The species is also known by many local names in the region of its distribution: Vellaiyagil, Purippa, Akil, Kana mulla, Purippa, Vellakil, Bili agilu.