Obetia tenax (Rock tree nettle, Mountain nettle)
[= Urera tenax]
Bergbrandnetel, Rotsbrandnetel [Afrikaans]; IuTiya [Swazi]; Lebabi, Mmabi
[North Sotho]; Mbhadzwa, Mmabi [Tswana]; Muvhazwi ("stinging") [Venda];
imBati, imBadi enkulu [Zulu]
> eukaryotes >
Charophyta > Streptophytina > Plantae (land plants)
> Tracheophyta (vascular plants) > Euphyllophyta > Lignophyta (woody plants)
> Spermatophyta (seed plants) > Angiospermae (flowering
plants) > Eudicotyledons > Core Eudicots > Rosids >
Eurosid I > Order: Rosales >
- A deciduous shrub or small tree, reaching a height of 7 m.
- All surfaces, including trunk, branches, leaves, flowers and
fruit, covered with stinging hairs, that cause intense pain and
blisters in contact with the skin.
- Bark smooth, bronzy-brown or pinkish brown.
- Watery latex present.
- Leaves alternate, ovate, fleshy, 3 strong basal veins, 5-15
cm long by 3-10 cm wide with petiole up to 14 cm long, margin
deeply toothed, apex broadly tapering, and base lobed.
- Flowers are small, whitish to greenish-yellow, in short
sprays in the axils of leaves.
- Fruit small, ovoid, purplish brown nut, about 2-3 mm in
diameter, clustered in spikes.
Distribution and habitat
From Komga in the Eastern Cape through to
KwaZulu-Natal, Swaziland, Mozambique, Zimbabwe and Botswana. Grows
on dry, rocky slopes and on granite outcrops, in bushveld.
- Leaves and stems eaten by:
Diceros bicornis (Hook-lipped rhinoceros, Black
rhinoceros) - according to Palmer & Pitman (1972) this is the
only browsing mammal that eats this plant.
- Used as a nesting site by:
Phoeniculus purpureus (Green wood-hoopoe, Red-billed
wood-hoopoe) - recorded nesting in pre-existing cavity in trunk.
- Fibre from the bark is used to make cord and rope.
- Leaves are boiled up as a vegetable (presumably boiling
de-activates the stinging hairs.
- The plant is used in traditional medicine.
- Palgrave, K.C. and Palgrave, M.C. 2002. Trees of Southern Africa. 3rd
Edition. Struik Publishers, Cape Town.
- Palmer, E. and Pitman, N. 1972. Trees of Southern Africa covering all
known indigenous species in the Republic of South Africa, South-West Africa,
Botswana, Lesotho and Swaziland. Volume 1. A.A. Balkema, Cape
- van Wyk, B. and van Wyk, P. 1997. Field Guide to Trees of Southern
Africa. Struik Publishers, Cape Town.