General Info

Tree up to 9m high. Palmately compound Leaves are decussate. 5-lobed, small, light mauve or purple Flowers have didynamous stamens + accrescent persistent calyx. The Fruit: small, dry drupe.

Description

Tree

Vitex rehmannii.

RSA Tree No. 664.

Common names: Pipe-stem Fingerleaf, Pypsteelboom.

Family: Lamiaceae (mint family) has 236 genera and 7 000+ species. Members if this family may have saw-toothed Leaves and may have 4-angled stems. The opposite or whorled leaves are usually simple or digitate. Many are gland-dotted and all lack stipules. Many are aromatic: including lavender and rosemary. Flowers are often Zygomorphic (the corolla is divisible into 2 equal halves in one plane only). There is a superior, 4-locular Ovary. Fruit has up to 4 one-seeded nutlets or is a drupe. Local genera include Clerodendrum, Tinnea, Vitex and Volkameria

Name derivation: Vitex – vieo: to bend or twist – referring to the stem flexibility in some species. rehmannii – after Anoni Rehman (1840-1917) – polish botanist and geographer. He travelled to South Africa twice between 1875-1880. His plant collection included about 3 000 different species.

Conservation Status: L C (Least Concern).

The Tree may reach 9m high and the trunk is up to 30cm (usually less) wide. The young stems are twisted, have soft hair, are whitish and leaf scars are visible. The branches of these trees have soft centres, which are ideal for making smoking pipes. They may be single or multi-stemmed. The bark becomes rough, dark brown and cracked to deeply fissured.

Leaves

The palmately compound (digitately compound leaves that are lobed or divided or ribbed in a palm-like or hand-like fashion with leaflets arising from a single point) Leaves have 3-5(usually) leaflets. These may be entire or toothed near the apex. Crushed leaves have a pleasant aroma. Leaves are decussate (opposite pairs of leaves have successive pairs at right angles to each other i.e. rotated 90 degrees along the stem when viewed from above) (Photo 531). The central leaflet is usually the longest, up to 13 x 3cm and is lanceolate to narrowly oblong-elliptic. These leathery leaflets are more than 3-times as long as wide. The upper leaf surface is glabrous (hairless). The lower side is slightly hairy and has a prominent midrib and lateral veins. All veins are visible when the leaf is held against the sun and examined with a hand lens (photo 526).  The Petiole (leaf stalk) may be up to 5cm long and the Petiolules (leaflet stalks) are up to 6mm long.

Flowers

The small, light, 5-lobed mauve or purple Flowers are 5-merous.  Each flower has a pedicle (stalk of a single flower) and more than one flower may occur in a single leaf axil. The Calyx is persistent and 5-lobed. The Corolla is short, bell-shaped, with a wide-open throat and is weakly bilabiate (2-lipped). The upper lip is 2-fid and the lower lip is 3-fid. The Stamens are didynamous (having 4 stamens disposed in 2 pairs of 2 different lengths). The Anthers are divergent (spreading very far apart). The dorsifixed, extrorse (turned outwards) anthers are attached to thick, glandular Filaments which are hairy at the base. The thick walled superior Ovary has a bifid Style, which is usually exserted.

Fruit

The small, pear-shaped, dry Fruit is a 4-locular drupe (a fleshy, 1-seeded indehiscent fruit with the seed enclosed in a stony endocarp; stone fruit e.g. peach) which matures to a black colour. It is up to 6mm long and rests on a accrescent (increasing in size with age like a calyx that continues to grow after the corolla has fallen), now papery, calyx.

Distribution & Ecology

This plant is located in KwaZulu-Natal, Gauteng, Mpumalanga, Limpopo, North West and Swaziland. It is Endemic (endemism is the ecological state of a species being unique to a defined geographic location) in southern Africa. It is common in thornveld, mixed-bushveld and is found in sandy flats and wooded, rocky areas e.g. quartzite (acidic rocks with a lowish pH value) hillsides. Coppice (when stems are cut or burned it causes regrowth from the stump or roots) leaves are broader than adult leaves.

Ethnobotany

To prevent termite attack, the Wood needs to be properly seasoned prior to use. The common name “pipe-stem” is due to the hollow stems, which are used for making smoking pipe stems. The wood is reasonably hard and yellowish with a straight grain and is easily worked. Stools and hammer handles are made from it. The wood makes a good fuel. Leaves are used in local medicine to relieve stomach-aches. Crushed leaves are aromatic. Extracts are reasonably active against gram-positive bacteria and malaria. Future research on the malaria aspect may produce interesting results.

References

Boon, R. 2010. Pooley’s Trees of eastern South Africa. Flora and Fauna Publications Trust, Durban.

Coates Palgrave, M. 2002. Keith Coates Palgrave Trees of Southern Africa, edn 3. Struik, Cape Town.

Lawrence, G. H. M, 1951. Taxonomy of Vascular Plants, The Macmillan Company, New York. Tenth Printing 1965.

Palmer, E. & Pitman, N. 1972. Trees of southern Africa, Balkema, Amsterdam, Cape Town.

Schmidt, S. Lotter, M. & McCleland, W. 2002. Trees and Shrubs of Mpumalanga and the Kruger National Park.

van Wyk, B. & van Wyk, P. 1997 Field guide to Trees of Southern Africa, Struik, Cape Town.

 

https://plants.jstor.org/stable/10.5555/al.ap.person.bm000006922

https://www.sciencedirect.com/science/article/pii/S0378874108003589

http://redlist.sanbi.org/species.php?species=4072-16