Botanical Name: Ptaeroxylon obliquum
Species: P. obliquum
Common Name: Sneezewood
Habitat: Ptaeroxylon obliquum is native to Southern Africa – Tanzania, Angola, Namibia, Zimbabwe, Botswana, Mozambique, Swaziland and S. Africa. T growsd on dry evergreen forest, often together with Podocarpus and Juniperus, and in bushland, at elevations from sea-level up to 2,000 metres.
Ptaeroxylon obliquum is an evergreen to semi-deciduous tree growing to 20 m (65ft) by 15 m (49ft) at a medium rate.
It has dark grey bark bearing deep longitudinal and inter-linked furrows. The leaves are opposite and compound. The leaflets are dark green with an entire margin and slightly wavy edges. The cream flowers are sweetly scented and appear on short branched heads. The fruit is an oblong reddish brown capsule.The plant is not self-fertile.
A plant of tropical and subtropical areas, where it is found at elevations from sea level to about 2,000 metres. Tolerates moderate levels of frost. Thrives best in shale or lime soils, though it also succeeds in well-drained sandy or rocky soils. Established plants are drought tolerant. The tree grows moderately fast, achieving annual increments of 40 – 100cm in height under good conditions. Trees can be managed by coppicing, showing regrowth in about 75% of cut stems. Natural regeneration often occurs in forest margins, but saplings have also been recorded in Pinus plantations in South Africa. Regeneration may be abundant after severe opening of the forest canopy, and seedlings may cover the bare forest floor after disturbance. Dioecious, both male and female forms need to be grown if seed is required.
The wood has the scent of pepper and causes sneezing. The bark, the sawdust and the smoke from burning wood are used as a snuff against headache. Bark and wood infusions are considered remedies for rheumatism, arthritis and heart complaints. The wood resin is applied to warts and is used to kill ticks on cattle. A tea made from the twigs is used against urinary complaints[299 ]. The wood and leaves contain chromones and other phenolic compounds. Some of these, methylalloptaeroxylin and perforatin A, showed antihypertensive effects; 7-Hydroxychromones have anti-oxidant activity. The tree lacks limonoids, which are commonly found in Rutaceae. An alkaloid isolated from the bark showed cardiac-depressant activity. Dichloromethane extracts of roots, leaves and stems showed moderate in-vitro antiplasmodial activity.
The wood chips are used to repel moths from clothes. The smoke from burning wood is used as traditional pesticide for stored grain. The resin can be used as an insecticide. The heartwood is rose-red to dark red, changing to orange-brown or golden brown on exposure, and distinctly demarcated from the pale grey, narrow sapwood. The grain is wavy, texture fine. The wood is hard, heavy, tough, dense and close-grained, it has a satiny lustre and a strong peppery smell. The wood is extremely durable and resistant to termite, Lyctus and marine borer attacks. Taking into account its hardness, the wood is not difficult to saw, but it is difficult to work because of its wavy grain. However, it can be finished to a smooth and lustrous surface. The turning properties are excellent. Pre-boring before nailing is necessary. Gluing is difficult. The wood is highly valued for furniture and for poles in house building. In Mozambique it is favoured for making the keys of traditional xylophones, and for this purpose it is baked in an oven. It has also been used for railway sleepers and durable fence posts. It is suitable for heavy construction including marine works, heavy flooring, vehicle bodies, handles, sporting goods, implements, toys, novelties, precision equipment, carving, pattern making, vats and turnery. When used as machine bearings, sneezewood often wears longer than brass or iron. The wood contains an oil that makes it very inflammable – as well as being used as a fuel, it is employed as a tinder and is used to produce fire by friction. The wood is reported to ‘burn like paraffin’- giving a bright, hot fire.
Known Hazards: The wood dust is very irritating and may cause violent sneezing. Highly irritant, aromatic peppery oils, containing nieshoutol, are produced by the wood, causing violent sneezing by woodworkers after sawing or sanding.
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.