It is not only the beauty of the flowers that creates interest
in this tree, but also the unique appearance of its fruit and the
lovely, palmately compound leaves.
murex grows up to 6-12m with wide, with spreading branches and
1-2m stems up to 30cm in diameter. The stem is covered with thick,
ribbed, gray-brown bark. In old wood, the bark becomes almost black
and is cracked into rectangular segments.
The leaves are borne on long hairy stalks, and are composed of
5-10 stalkless leaflets radiating, finger-like from one point. They
are oblong to widely lance-shaped, narrowed to both ends, pointed,
usually up to 10 cm long and 5cm wide. The leaves are velvety both
sides, the midrib, secondary veins and the netted veins conspicuous
on the lower surface.
Sterculia murex flowers in sprays at the ends of the usually
bare branches from August to October. They are waxy and yellow,
marked with brown or crimson flowers. As in all the Sterculias,
the petals are absent while the sepals are petal-like.
The five-lobed fruits are unique in appearance. They are large
(up to 30cm in diameter if all lobes develop), woody and covered
thickly with hard spines. The shell contains large oval seeds, resting
in a bed of stinging hairs that can be irritating on contact with
the skin or eyes. It is seldom that a very big complete fruit is
collected as they grow high on the tree and shatter as they fall.
The open fruit shell makes an unusual ash-tray, and is not easily
charred by lighted cigarettes. The sweet, oily seeds are relished
by baboons and monkeys, and after roasting, are enjoyed by humans
too. The tree is mainly grown for decorative effect as the wood
is soft and of little use. Palmer and Pitman (1972) report that
these trees are not popular with cotton farmers for they are a breeding
place of the "cotton stainers".
The lowveld chestnut grows well on the hills near the Pretorius
Kop entrance to the Kruger Park. It grows in a limited number of
areas in Mpumalanga, most often on wooded, rocky hills, and also
The genus Sterculia was named after the Latin god Sterculius.
The specific epithet "murex" is also Latin meaning,
"having rough parts" or "prickly" in reference
to the spiky fruits. Despite its common name this tree is not related
to the true chestnuts.
There are about 150 species in this fascinating African and Asian
genus. Of the five species of Sterculia found in southern
Africa, only Sterculia murex and Sterculia alexandri
have attractive, digitately compound leaves. Sterculia alexandri
is a very rare tree, a red data listed plant, only found in several
isolated areas of the Eastern Cape near Port Elizabeth. The family
Sterculiaceae also contains the genus Dombeya, several species
of which are cultivated and have been described in this series.
Growing Sterculia murex
is an unusual and quick growing tree for warm gardens. It is not
frost tolerant and prefers well drained soils and a relatively high
rainfall. Although it comes from the subtropical summer rainfall
part of the country, trees are growing and flowering at Kirstenbosch
which has a winter rainfall, mediterranean climate.
Sterculia murex is usually grown from seed. Fresh seed
germinates readily. The roots are formed first and the leaves only
appear above the soil or the growing medium after a few months.
For better germination, the seed should be placed on top of the
soil. To prevent fungal diseases, treat the seed with a fungicide
before planting. A growing medium of 50% bark mixed with 50% polysterine
is suitable. The seed tray should be kept damp and placed on a bench
or a raised bed to protect the seed from rats and mice, who seek
out the protein rich seeds.
- Coates Palgrave, K. 1983. Treesof Southern Africa, Cape Town,
C Struik Publishers.
- De Winter, B. et al. 1966, Sixty-six Transvaal Trees, Pretoria,
Botanical Research Institute, Department of Agricultural Technical
- Hilton-Taylor, C.1995, Red Data List of Southern African Plants,
Pretoria, National Botanical Institute.
- Palmer, E. and Pitman N, 1972, Tree of Southern Africa, Cape
- Van Jaarsveld, E. 2001, Personal Communication.
- Van Wyk, P. 1984, Field Guide to the trees of the Kruger Nationl
Park, Cape Town, C Struik Publishers.
Kirstenbosch National Botanical Garden
with additions by Yvonne Reynolds