Androstachys
| Lebombo ironwood | |
|---|---|
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Rosids |
| Order: | Malpighiales |
| Family: | Picrodendraceae |
| Tribe: | Picrodendreae |
| Subtribe: | Mischodontinae |
| Genus: | Androstachys Prain |
| Species: | A. johnsonii |
| Binomial name | |
| Androstachys johnsonii Prain | |
Androstachys johnsonii, the Lebombo ironwood, is a tree species and the sole member of the genus Androstachys in the Picrodendraceae. It is native to Africa and Madagascar. Within southern Africa, it occurs in Limpopo Province, Mpumalanga and Swaziland. It is widely used in the Southern part of Mozambique, where it is known as Simbirre, for flooring and is commonly traded for pillars of huts and fences. South African tourist operators in Mozambique used it extensively for building structures near or in sea water.
Uses
The wood is extremely hard and durable and its timber.[1] It is of economical interest, traded as mecrussé, and makes good flooring. It is rarely traded, presumably because of a lack of supply.
Habitat
Commonly found at altitudes up to 1000 m. Forming dense shrub like thickets, thrives in hot and dry climates with well drained soils; rocky hillsides or along seasonal watercourses.[2]
Description
It is described as a medium-sized, evergreen tree growing up to 20 m high.[1][2] It is characterised by a rough bark with a whitish, woolly, hair like covering on the new growth.[1] The leaf blades are 3-9 x 2-7 cm and are oppositely paired at right angles.[1][2] They are ovate to heart-shaped with both the apex and base rounded.[1][2] The upper surfaces are shiny and are a green to blue-green color, beneath the surface is covered in dense, white, woolly hairs.[1][2]
Flowering
Flowering time is October–November.[2] Flowers axillary, unisexual and vary in both arrangement and appearance.[1][2] Male flowers are yellow and are arranged in a 3-flower cluster up to 3 cm long.[1][2] Central flowers are longer than the laterals with their pedicel being 1-1.3 cm long versus the lateral length of 5-6 mm.[2]Sepals; greenish petals that the form the calyx of the flower differ in number; 5 in central flower and 2-3 in laterals.[2] The bulbous base or receptacle of flower from which its organs grow are 2 cm long in central; 1.5 cm in laterals.[2] Stamens up to c. 50 in central c. 35 in lateral, filaments of lowest stamens up to 1 mm long, anthers 3 x 0.5 mm covered in fine silky hairs in early development and then smooth, lacking hairs with maturation.[2] Yellowish thecae of anthers. Female flowers are yellow and are at the end of a long, white hairy stalk.[1] Pedicels are 1–1.5 cm long, extending to up to 3 cm long in fruit; sepals 7–8 × 2–2.5 mm and are an ovate-leaf shape, blunt tapering or sometimes split at apex, minutely ruffled with fine hairs on edge and base; otherwise smooth.[2] Ovary is c. 3 mm in diameter, oval in shape, densely covered in fine white woolly hairs.[2] Styles c. 7 mm long with fine hair covering, stigmas are globe shaped.[2]
Fruit
Fruit is bright green at first and ripens to a yellow- light reddish brown and is covered in fine bristle like hairs.[1][2] It is a 3-lobed capsule 8-10 x 12–13 mm in size and is easy to detach.[1][2] Seeds are a chestnut brown with long, shallow, linear ridge. Their dimensions are 6.5-7(8) x 4.5-5(6) x 2-3 mm.[2]
See also
References
- 1 2 3 4 5 6 7 8 9 10 11 "Androstachys johnsonii". Flora of Zimbabwe: Species information. Retrieved 2011-11-09.
- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Radcliffe-Smith, A. (1996). "Euphorbiaceae". Flora Zambesiaca: Taxon Detail. Retrieved 2011-11-09.
- "Androstachys johnsonii". Flora of Zimbabwe: Species information. Retrieved 2010-02-09.