General Info – summary.

This Tree with light to dark bark is up to 15m high – usually 6m.  Pairs of opposite, decussate spines may be present.  Simple ovate to oblong Leaves with entire margins are in opposite pairs near branch ends.  Here domatia may be present.  Minute greenish-yellow Flowers are in cymes and each rests on a short pedicel.  They usually arise with new leaves.  Wrinkled Fruit is an animal attracting drupe, aiding seed dispersal.

Description.

Canthium inerme.

Previous Names: Canthium swynnertonii, Canthium thunbergianum, Canthium ventosum, Lycium inerme, Plectronia swynnertonii, Plectronia ventosa.

SA Tree No. 708.

Common names: (Afr) Bokdrol, Bokdrolbessie, Bokdrolletjie, Boringklipels, Bosdoringklipels, Doringels, Gewone Bokdrol, Skaapdrolletjie, Wolwedoring, Wildelemoentjie.  (Eng) Cape Date, Common turkey-berry, Criss-cross Turkey-berry, Turkey Berry, Unarmed Turkey-berry.  (isiXhosa) Umnyushulube, Isiphingo.  (isiZulu) Umvuthwamini, Umvuthwemini.  (Northern Sotho) Mmutswa-o-sepela.  (siSwati) umVutfwamini, Mvutwamira.  (Tshivenda) Muvhibvela-shadani.

Family: Rubiaceae. (Coffee/Gardenia family).  This family of dicotyledonous plants has in excess of 600 genera and about 13 000 species and members include trees, shrubs and herbs.  Local genera with trees on this website include Afrocanthium, Canthium, Coddia, Gardenia, Pavetta, Rothmannia and Vangueria.  Leaves are simple, opposite or whorled and have interpetiolar stipules.  Flowers are bisexual or unisexual.  The calyx has sepals that are at least partly united.  Petals are joined – at least at the base.  Stamens are usually as many as and alternating with corolla lobes.  The Ovary is inferior.  Fruit is a drupe, berry or capsule.

Name derivation: Canthium – from the Malabar (Indian) name: canti for a species of this genus.  inerme – unarmed – inaccurate name.  In southern Africa, about 15 species of Canthium are listed as trees.

Conservation: National Status: L C. (Least concern).  Assessed: 2005 (W. Foden and L. Potter).

Tree

This well-known semi-deciduous Tree (photo 946) or small shrub has a spreading crown and may reach 15m high in the forest but is usually up to 6m high.  It may also be a creeper.  The Stem is round or fluted and the colour varies from whitish to silver-white or pale grey.  It may be straight or branched and can each a diameter in excess of 30cm.  Twigs (1-year-old current branch segments) are thickish and covered with raised Lenticels (usually raised corky oval or elongated areas on the plant that allow the uncontrolled interchange of gases).  The Bark on young trees is smooth, clearly visible light grey and ages to become rough (photo 939) and brown in forests.  Opposite pairs of equal straight Spines are up to 8cm long. They may develop just above the nodes and are more common in forest trees.  They emerge at a right angle to the stem.  Branches are decussate (arranged in opposite pairs at right angles to those above and below).

Leaves

The softly leathery Leaves (photo 944) are hairless or with domatia (tiny chambers produced by plants that house arthropods.  To the naked eye each domatium appears as a small bump) in vein axils.  Leaves are simple (have a single blade, which may have incisions that are not deep enough to divide the leaf into leaflets).  They are light green above, lighter below, and develop with new growth in opposite pairs – close to branch ends.  Leaves are ovate to oblong, lance-shaped or elliptic and up to 10 x 4,5cm (photo 940).  The Apex and Base either taper or are rounded (photo 944).  The Blade is light green and glossy above and lighter below (photo 940).  Here the Midrib (the main rib of a leaf or leaf-like part, a continuation of the petiole) protrudes.  The pale side veins tend to loop before reaching the margin (photo 943).  The wavy and rolled under Margins are entire (with a continuous margin, not in any way indented).  Here the base of the margin is slightly decurrent (the leaf blades partly wrap around the petiole).  The smooth Petiole (leaf stalk) is less than 1,5cm long.  The triangular Stipules are shortly sheathing and up to 4mm long.

Flowers

The very small (up to 3mm long), slightly sweet-scented, greenish-yellow Flowers with white, hairy throats are borne on leaf axils in dense clusters – often with new leaves.  Inflorescences have 4-40 short-branched heads (up to 3cm in diameter) contained within a Cyme (a broad, more or less flat-topped, determinate flower cluster, with central flowers opening first) that has 2 secondary axes.  Each flowers rest on a short Pedicel (stalk of a single flower) and often arises with the new leaves.  The Calyx is saucer or basin shaped.  The petals in the yellow-green Corolla have a broadly cylindrical tube ending with reflexed lobes. The flowers are Monoecious (having both male and female reproductive organs on the same plant) and here each flower is functionally male or female.  In functionally male flowers, the Stamens arise from the corolla mouth.  The Filaments are usually shorter than the Anthers.  The Disc (a more or less fleshy or elevated development of the receptacle) is annular.  In functionally female flowers, the inferior, 2-locular Ovary has a single pendulous Ovule in each locule.  The hairless Style is narrowly clavate (thickened towards the top, like a baseball bat) and slightly longer than the corolla tube.  (Aug-Jan).

Fruit

The Fruit rests on a long Pedicle (flower stalk) and is an oblong to ovoid, 1 or slightly 2-lobed Drupe (stone fruit).  It is a fleshy, indehiscent fruit with the seed enclosed in a stony endocarp – like a peach.  Beyond this is a fleshy mesocarp surrounded by the skin or exocarp.  The drupe may be 2-seeded, is initially shiny green and usually up to 1,5 x 1cm.  It ripens to become purple or black, wrinkled and has a round scar at the apex.  Fallen fruits resemble goat or sheep droppings – hence 3 of the common names.  (Oct-Apr).  The Fruit may remain on the tree for many months.

Distribution & Ecology

This is a typically scattered tree – often close to the sea.  They are located in the Western Cape, Eastern Cape, KwaZulu-Natal especially the southern coast, Mpumalanga, Gauteng, North West and Limpopo.  It also occurs in Eswatini (Swaziland), central and southern Mozambique and Eastern Zimbabwe.  They are absent from most arid areas and wettest forests.  Apart from this, these trees occur from sea sands, within kloofs (steep-sided, wooded ravines or valleys), subtropical bushveld and scrub up to an altitude of 2 000m – usually among rocks at higher altitudes.  They are common on grasslands, among rocks and near to streams.  Domatia (tiny chambers produced by plants that house arthropods may be present).  To the naked eye, the domatia appear as small bumps and are present in vein axils.  These domatia are not hairy.  Many birds including the Rameron Pigeons or African Olive Pigeons (Columba arquatrix) are attracted to the Fruit that is borne in great abundance.  Birds relish the fallen fruit.  Agents of pollination include bees; and birds often disperse seed.  These tree Leaves and those of Volkameria glabra, Munduela sericea+ are hosts for the larvae of the Natal Barred Blue / Natal Silverline Butterfly (Cigaritis natalensis).

Ethnobotany

The Trees are used to shelter stock.  The attractive, extremely hard Wood is dense, close-grained, tough and takes varnish well.  It is yellow or light brown and has a marbled grain.  Uses include fence poles, implement handles, fuel and wagon wheel felloes (the outer rim of the wheel).  Large pieces of wood seldom develop.  Traditional medicine makes use of the Leaves.  The Fruit is slightly insipid but edible.

References

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

Burrows, J.E., Burrows, S.M., Lotter, M.C. & Schmidt, E. 2018. Trees and Shrubs Mozambique.  Publishing Print Matters (Pty) Ltd.  Noordhoek, Cape Town.

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

Foden, W. & Potter, L. 2005. Canthium inerme (L.f.) Kuntze. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2022/11/07.

Ginn P.J. Mcilleron W.G. and Milstein P. le S, 1989. The Complete Book of Southern African Birds. 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. Jacana, Johannesburg.

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

Woodhall, S. 2020. Field Guide to Butterflies of South Africa, edn 2. Donnelley, RR, China.

 

https://www.flickr.com/photos/52450054@N04/42582854252

http://plantinfo.co.za/plant/canthium-inerme/

http://tropical.theferns.info/viewtropical.php?id=Canthium+inerme

http://posa.sanbi.org/flora/browse.php?src=SP

https://en.wikipedia.org/wiki/Cigaritis_natalensis

https://en.wikipedia.org/wiki/Rubiaceae