This attractive indigenous shrub may be found in
a variety of habitats ranging from arid karoo, coastal dune bush,
evergreen montane forest and wooded grasslands. On the Highveld,
mainly grows in clumps of bush and rocky places, often in the shade
of trees - it occurs naturally in the Witwatersrand National Botanical
Garden where it is common and may be found in almost all areas.
The natural distribution of the Grewia occidentalis ranges
from the Western Cape up to Zimbabwe and Mozambique. This genus
is named after Nehemiah Grew (1641-1712), an English physician.
Occidentalis means from the west.
It is a scrambling deciduous shrub or small tree reaching up to
3m in height. Purple star-shaped flowers (measuring 1.5 to 3cm across)
appear in summer (October - January), followed by distinctive four-lobed
fruits (hence the common name cross-berry and four-corner). Fruits
turns shiny reddish-brown to light purple when ripe (January - May)
and may remain on the tree for long periods.
The leaves are alternate and simple with three distinct veins from
the base. They are shiny deep green and may be slightly hairy on
both surfaces. They are usually held in a horizontal plane towards
Leaves are browsed by cattle, goats and game (black rhino, giraffe,
nyala and grey duiker). Ripe fruits are relished by various birds
such as louries, mousebirds, bulbuls and barbets as well as certain
mammals (including man). Larvae of the rufous-winged elfin butterfly
(Eagris nottoana) and buff-tipped skipper (Netrobalane
canopus) feed on the leaves of this species.
In certain areas where the sugar content of the fruits is high,
they are collected and dried for later use. The dried fruits are
sometimes boiled in milk - a bush milkshake! Beer is also brewed
from the ripe fruit in certain areas. Other human uses of this species
include using the wood to make bows and spear shafts.
The cross-berry is an important species in traditional medicine
and is used for a variety of purposes. Bruised bark soaked in hot
water is used to treat wounds. Pounded bark, used regularly as a
shampoo, was believed to prevent hair from turning grey. Parts of
the plant were used to treat impotence and sterility, and root extracts
were used to help in childbirth.
Growing Grewia occidentalis
Grewia occidentalis makes a decorative garden plant which
is both frost- and drought-hardy. It will grow well if well-watered
and planted in good, composted soil. The cross-berry may be planted
in either full sun or shade. The root system is not aggressive and
can therefore be planted near buildings and paving. It is a "must-have"
species in the garden to attract butterflies and birds.
This species is best propagated from seed. Studies have shown that
seed which has passed through the gut of monkeys and baboons germinates
better than those collected from a tree. This is due to the fact
that the seeds chemical inhibitors have been broken down by the
animal's stomach acids. However germination is generally fairly
good - so perhaps it is not necessary to find a monkey to assist
you with your propagation attempts!
- Pooley, E. (1993) Trees of Natal, Zululand and Transkei. Natal
Flora Publications Trust : Durban.
- Thomas, V & Grant, R. 2000. Sappi Tree Spotting - Highveld.
Jacana Education : Johannesburg.
- Van Wyk, B. & S. Malan (1988) Field Guide to the Wild Flowers
of the Witwatersrand and Pretoria region. Struik Publishers :
- Van Wyk, B. & P. van Wyk (1997) Field Guide to Trees of
Southern Africa. Struik Publishers : Cape Town.
- Venter, F. & J. Venter (1996) Making the Most of Indigenous
Trees. Briza Publications : Pretoria
- Heywood,V. H., Brummitt, R.K., Culham, M.A. & Seberg, RG, O. 2007. Flowering plant families of the world. Firefly books Ltd, Ontario,Canada.
Walter Sisulu NBG
Updated July 2008