General Info.

This Tree is up to 6m+ high.  Leaves are simple but have up to 5 deep lobes.  Unpleasantly scented Flowers are greenish yellow, 5-merous and in spikes.  The small Fruit is glabrous, fleshy and in spikes.

Description

Cussonia natalensis

RSA Tree No. 562.

Common names: Rock Cabbage Tree, Simple-leaved Cabbage-tree, Sambreelboom, Natal cabbage tree.

Family: Araliaceae. (Ivy and cabbage-tree family) with 50+ genera and about 700 species. In southern Africa, there are 5 genera and about 18 species.  These genera include Cussonia and ScheffleraLeaves are usually alternate and petaloid.  They may also be once or twice digitally compound.  The regular Flowers usually have 5 petals and the calyx is attached to the inferior, 2-locular Ovary.  Each locule has a single ovule.  There are as many Stamens as petals.  Anthers contain 2 pollen sacs. Fruit varies.

Name derivation. Cussonia. The name Cussonia was given by Carl Peter Thunberg to commemorate the French botanist Pierre Cusson.  He was professor of Botany at the University of Montpellier.  He specialised in the Apiaceae or Umbellifera.  (1727-1783).  natalensis – first discovered in Natal – now KwaZulu-Natal.  About 10 species of the genus Cussonia occur in the southern Africa.

Conservation Status: L C. (Least Concern).  2009 (Raimondo et al.).

Tree

This Tree has a rounded and spreading crown may reach from 6 to 10m high.  The Trunk is sturdy up to 0,6m in diameter and is much branched and spreading.  The Bark is corky and mainly longitudinally fissured.

Leaves

This deciduous tree has Leaves that are relatively simple (have a single blade which may have incisions that are not deep enough to divide the blade into leaflets).  However, the incisions extend quite a way, giving rise to their star shape.  Other species of Cussonia do not share being deciduous and having simple leaves.  The leaves are deeply 3-5 lobed but not divided (photo 546).  When 5-lobed, the upper 3 lobes are slightly larger (photo 546). The lobes are narrow and are pointed.  Leaves are palmate (lobed or divided or ribbed in a palm-like or hand-like fashion), hairless, and crowded on long stalks at the ends of knobbly short branches.  This is distinctive.  The glossy light green and shiny leaves turn yellow in autumn before falling.  The Midrib in each lobe is easy to see on both sides.  Other veins are clearer below.  Young leaves are brownish green.  Each leaf is up to 20cm wide and makes this Cussonia one of the easiest to identify.  The bluntly and irregularly toothed Margin may be wavy.  The Apex is attenuate (showing a long gradual taper towards the apex).  The Base is broadly obtuse to cordate (heart shaped).  The Petiole (leaf stalk) is thin and up to 30cm long.

Flowers

The regular, greenish yellow and unpleasantly scented Flowers are grouped in up to 12 terminal heads of radiating cylindrical Spikes (simple indeterminate inflorescences with sessile flowers on single unbranched stalks).  Each spike is up to 15cm long and emerges from thickened side shoots that radiate from the ends of a branch.  The Flowers are 5-merous.  The Calyx has 5 toothed or almost entire Sepal lobes.  These sepals are situated above the ovary.  Each flower has 5 Petals that are valvate (meeting at the edge without overlapping).  There are 5 Stamens with ovate Anthers that are slightly shorter than the Filaments.  Each anther has 2 Thecae (pollen sacs which produce microspores –the pollen grains).  The inferior Ovary has 2 locules and 2 styles. (Feb-May).

Fruit

The small (about 0,6cm in width), fleshy and nearly spherical Fruit has a flat top.  Each fleshy fruit is glabrous (smooth and hairless).  When mature, the fruit is purplish and remains crowded on the spikes.  (Jun-Dec).

Distribution & Ecology

This is frost sensitive Tree, which is endemic (endemism is the ecological state of a species being unique to a defined geographic location) in southern Africa.  It is found on rocky hills usually at an altitude between 1 400m and 1 900m – away from the coast.  It thrives in hot, dry areas.  Trees are located in KwaZulu-Natal, Mpumalanga and Limpopo.  They are also located in Swaziland and Zimbabwe.

Ethnobotany

The Wood used for making dishes, bowls and cups.  Flowers have an unpleasant smell.  Trees are decorative, easily cultivated but frost sensitive.  There is one report of aggressive roots.  A pentacyclic triterpene acid, with anti-ulcer properties has been extracted from Cussonia natalensis.

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.

 

http://www.zimbabweflora.co.zw/speciesdata/species.php?species_id=142920

http://redlist.sanbi.org/species.php?species=4012-3

https://www.researchgate.net/publication/256829696_A_pentacyclic_triterpene_acid_with_anti-ulcer_properties_from_Cussonia_natalensis

https://ujdigispace.uj.ac.za/handle/10210/8059

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