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This evergreen tree makes a beautiful focal point in a garden as
it has an unusual shape, interesting gnarled bark and stunning,
large, grey-green leaves. Plants show up especially well in a layout
where rocks are used. Gardeners growing indigenous South African
plants favour them greatly for their unique appearance.
Description
This is a short, thick-set tree, rarely exceeding 5 m in height.
It is sparsely branched with grey, longitudinal fissured, thick
and corky bark. The stem is thick and squat. This plant is considered
a pachycaul succulent on the basis of its swollen stem base or tuber
which forms early in plants grown from seed. Roots are also thick
and swollen. The tree is slow growing.
The large, digitately compound, cabbage blue leaves are one of
its most distinctive features. The leaf colour is in some part due
to the thick waxy layers on the leaves, which may help protect them
against severe frosts. The leaves are composed of 7-9, but sometimes
up to 13 leaflets, springing from the end of a long stalk. The leaflets
are up to 30 cm in length and the overall leaf can reach 60 cm.
The leaflets of some forms are deeply lobed. New leaves are brighter
green and emerge in a spring flush at the ends of branches.
There are two subspecies of Cussonia paniculata. The smaller
mountain cabbage tree C. paniculata subsp. paniculata
has leaflets without lobes and has a limited distribution in Eastern
Cape. C. paniculata subsp. sinuata forms a larger
tree with deeply lobed leaves and is more widespread. This is the
form more commonly found in cultivation.
From January to April these trees bear small, green, stalked flowers;
in short dense spikes, making up a large, branched inflorescence
at the end of the trunk or branches. Flowers are followed by fleshy
and purple-maroon fruits, which mature in May to June.
Distribution
Cussonia paniculata occurs inland at altitudes up to
2 100 m. It is often found in rocky places from the mountains of
the Karoo and Eastern Cape through KwaZulu-Natal and Free State
into Gauteng and further north. It grows in crevices filled with
natural organic humus and compost. It is commonly found near Johannesburg
and Pretoria. It is frost-tolerant and drought resistant.
Derivation of name and historical aspects
The name Cussonia was given by Carl Peter Thunberg to
commemorate the French botanist Pierre Cusson (1727-1783). The specific
name refers to the panicle or branched inflorescence. It is believed
that the name 'kiepersol' comes from the Portuguese (Quinta-sol)
or Indian (Kitty-sol), words for a parasol or sunshade. The genus
has about 25 species of which about eight occur in South Africa.
The remainder are found throughout tropical and southern Africa,
Madagascar and the Comoro Islands.
Ecology
The flowers are pollinated by an enormous variety of insects that
have wings e.g. bees, wasps, flies. When they are in full flower
it sounds like a beehive. The flies and insects are attracted by
the flowers' smelly nectar. The flowers may have lots of pollen
too. The seed are not as easily parasitized by pests as Acacia
and Rhus species. The birds feed on the ripened, black seed.
Use and cultural aspects
The wood is soft and light and was used for the brake-blocks of
wagons. The leaves provide good fodder for stock and the Zulu name
refers to this tree as goats' food. The thick root can be peeled
and eaten raw as food or as a source of water (Van Wyk & Gericke
2000). Recent research (Tetyana et al. 2002) sets out to investigate
the traditional medical uses of Cussonia and Schefflera
to treat infections, inflammation and malaria.
Growing Cussonia paniculata
The best method of propagation is by means of seed harvested from
fresh ripe fruits. Detailed instructions on propagation are found
in Oliver (1987). Sow seed as soon as possible as it loses much
of its viability within 3 months. However, seed sown in summer months
will germinate faster (in about 4 weeks) than seed sown in winter
(7 weeks to germination). Make sure seed trays are at least 15 cm
in depth to allow the small tubers to form. Do not allow seed to
become waterlogged or dry out. Keep seed and seedlings in a semi-shaded
area. Seedlings can be transplanted at about 4 months, but be very
careful not to damage the fleshy roots when transplanting.
One can grow Cussonia paniculata from a cutting, but this
is not advisable because it does not make the proper, fleshy, underground
rootstock that it forms when grown from seed.
Tetyana & Van Staden (2001) write about the micropropagation
of this species, mentioning the benefits that could be derived from
propagating forms with variegated leaves as ornamentals.
References
- ACOCKS, J.P.H. 1988. Veld types of South Africa, edn
3. Memoirs of the Botanical Survey of South Africa No. 57.
- VAN WYK, B. & VAN WYK, P. 1997. Field guide to trees
of southern Africa. Struik, Cape Town.
- PALMER, E. 1977. A field guide to trees of southern Africa.
Collins, London and Johannesburg.
- COATS PALGRAVE, K. 1981. Trees of southern Africa, edn
2. Struik, Cape Town.
- MOFFETT, R.O. 1993. Anacardiaceae: Rhus. Flora of southern
Africa 19, part 3, fascicle 1. National Botanical Institute, Pretoria.
- VAN WYK, B-E. & GERICKE, N. 2000. People's plants.
Briza, Pretoria.
- ESTERHUYSE, C.J. & REYNEKE, W.F. 1987. Cussonia species:
Tree of the Year 1987.Pamphlet No. 376. Forestry Branch, Dept
of Environment Affairs, Pretoria.
- TETYANA, P. et al. 2002. Some medicinal properties of Cussonia
and Schefflera species used in traditional medicine. South
African Journal of Botany 68: 51-54.
- TETYANA, P. & VAN STADEN, J. 2001. Micropropagation of
Cussonia paniculata-a medicinal plant with horticultural potential.
South African Journal of Botany 67: 367-370.
- WALKER, C.J. 1988. Cussonia paniculata: the mountain cabbage
tree. British Cactus and Succulent Journal 6: 98-100.
- OLIVER, I.B. 1987. Cultivation of the mountain cabbage tree.Veld
& Flora 73: 135, 136.
- JOFFE, P. 1993. The gardener's guide to South African plants.
Delos, Cape Town.
Peter Gavhi & Shireen Harris
Free State national Botanical Garden
(With additions by Yvonne Reynolds)
October 2002
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