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This is a vigorous, very decorative, reed-like plant with thick
main stems and finely divided side branches. It can be used for
a mass planting or as an accent plant in the garden, while the young
shoots are ideal for flower arrangements.
Description
Cannomois virgata is the botanical name for a group of three
or more reed-like plants varying in height from 1.5 to 5 m tall.
The average horticulturist may think these groups look quite different,
but botanists have had a problem finding enough botanical differences
between the groups to divide them
into different species. Prof. Peter Linder at the University of
Zurich, Switzerland, has recognized these different features and
has split the group into three species; (1) plants which grow to
a height of 1 to 1.5 metres; (2) plants which grow to a height of
1.5 to 2 metres and (3) those which grow to a height of 5 metres.
Unfortunately, Prof. Linder has not published these names yet and
all three groups are still called by the same name, Cannomois
virgata.
These reed-like plants are clumped or mat-forming. The rhizomes
are grow vigorously and the plants can reach a diameter at ground
level of about 2 m and a crown diameter of up to 3 m. The common
name of olifantsriet refers to the large form of Cannomois
virgata, and bergbamboes refers to the tall thick stems,
like a bamboo. The strong culms or stems have clusters of sterile
branches at the nodes, which can reach a length of one metre and
give the plants a very graceful appearance.
The plants flower at the beginning of summer, October to November.
The inflorescences grow up to 0.5 m long. The male inflorescences
are pale gold in colour and resemble a long raceme with short side
branches with small, golden flowers.
The
female inflorescences are much shorter and have tight, pale brown
bracts which conceal the small insignificant flowers. It takes nearly
a year for the seeds to ripen. The female inflorescences of the
smaller form flower very poorly, whereas the tall form produces
a large amount of inflorescences, which look very ornamental and
are used in the dried flower trade. C. virgata grows fairly
fast and will have attained its final height two to three years
after planting.
Distribution and Habitat
: The smallest form of Cannomois virgata is widespread and
occurs from the Cape Peninsula throughout the southwestern mountains
to the Outeniqua Mountains in the Eastern Cape. The tall, bamboo-like
form has more or less the same distribution but does not occur on
the Cape Peninsula, and the medium tall form does not occur on the
wetter parts of the mountains. The plants grow in fairly poor soils,
in sandstone as well as shale-derived soils. The tall form is often
found near streams in gorges or deep valleys. Although plants can
be grown in the northern hemisphere, they have to be protected against
frost and can not survive in frozen or very cold, wet soils.
Derivation of name and historical aspects
The name Cannomois comes from the Greek, canna for
cane and omoios meaning similar. Virgata means twiggy.
Cannomois virgata belongs to the large southern hemisphere
family of Restionaceae, which has more than 400 species of about
40 genera in southern Africa, Australia, Madagascar, Indo-China
and Chile. About 320 species occur in South Africa, most of them
in the Cape Floristic Region. At the moment only six species of
Cannomois have been described. The best known restio in South Africa
is Thamnochortus insignis,
which is widely used as long-lasting thatching material.
Ecology
Like all other Restionaceae, Cannomois virgata is wind pollinated.
The seeds are quite large, the tall form having the largest seeds.
The hard seed coat is black or very dark brown and is either thin
and very brittle or very thick and woody. The nuts have an elaiosome,
which is a protein-rich white part on the outside of the seed and
is very attractive to ants. Once the seeds are ripe, they fall out
of the inflorescence and are carried away by ants almost as soon
as they hit the ground. The ants carry them to their nests, eat
away the elaiosome but leave the seed undamaged and safe from larger
seed eaters like mice or shrews.
Uses and cultural aspects
Cannomois virgata has been used by South Africans for hundreds of
years, in the past as brooms and is now gaining popularity in the
cut-flower industry. Smith (1966) writes that the restios were probably
used long before the first botanists saw restios being used as brooms
and as thatching material. The finely branched stems are particularly
suitable for the making of brooms. The stems are cut and dried in
the sun, the inflorescences are cut off and the stems are tied to
a broomstick or a strong handle. The common name besemriet refers
to this use. while the common names Rekoala and bell reed, which
refers to the part of the stem which carries the golden brown inflorescence,
are being used in the cut-flower industry. Rekoala resembles the
common names used for the indigenous restios for the cut-flower
industry of New Zealand, where only the finely branched stems are
used. The most coveted part of the plant by flower arrangers is
the young shoot, which is very beautiful, thick, bamboo-like, cream
to light green in colour with distinct nodes. However, when too
many young shoots are cut at yearly intervals, the plants soon die.
As the plants are becoming available from commercial plant nurseries,
they will find a well-deserved place in the gardens of the world.
Growing Cannomois virgata
The tall form of Cannomois regenerates from seed and is
killed by fire, whereas the smaller form coppices from the rhizome
after a fire and produces very little seed. Generally it is very
hard to germinate Cannomois seed and at Kirstenbosch the
germination percentage is very small, even when the seeds are sown
at the right time of the year, autumn, and are treated with smoke.
Vegetative propagation can be tried during the cold part of the
year, when the rhizomes can be divided into large chunks and planted
in a well-drained soil which must be kept very wet.
The tall form of Cannomois virgata is very decorative, both
the male and female plants can best be used as accent plants either
in a border, or near a rocky outcrop in a rockery. When planted
in large groups the male plants seem to be in the majority. If a
female plant consistently produces a lot of seed, the life span
is only eight to ten years, whereas the male plants or female plants
which produce less seed, can live much longer.
Although the plants in nature often grow near streams and would
look very decorative when planted near a pond, they do not like
standing water and grow better in drier soils but with regular irrigation.
The plants should be regularly given organic fertilizer or compost
to improve the soil. They seem to be remarkably free from pests
or diseases.
References
- Brown, N., Jamieson, H. & Botha, P. 1998. Grow restios.
Kirstenbosch Gardening Series. National Botanical Institute, Cape
Town.
- Goldblatt, P. & Manning, J. 2000. Cape plants. A conspectus
of the Cape flora of South Africa. Strelitzia 9. National
Botanical Institute, Pretoria.
- Dorrat-Haaksma, E. & Linder, H. P. 2000. Restios of the
Fynbos. The Botanical Society of South Africa, Cape Town.
- Linder, H.P. 1985. Conspectus of the African species of Restionaceae. Bothalia 15: 387-503.
- Linder, H.P. 1991. A review of the southern African Restionaceae.
Contributions from the Bolus Herbarium No. 13.
- Smith. C.A. 1966. Common names of South African plants. Memoirs
of the Botanical Survey of South Africa No. 35.
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Hanneke Jamieson
Kirstenbosch NBG
July 2004
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