The Modjadji cycad Encephalartos transvenosus

Cycads are an ancient group of seed plants meaning that they are spermatophytes. During the Jurassic period, cycads were common in many parts of the world e.g Japan. Today cycads are very few in tropical and subtropical regions and in southern and northern hemisphere. While large numbers of cycads are found on the continents of Australia, South America, and South Africa. Many cycads live 200 million years ago before the dinosaurs roamed the earth. Cycads grew well during eons period that is 150 million years ago (1). The arrival of dinosaurs caused a decrease in the number of cycads (1) because they fed on cycads. During that time, herbivores were dominant.


Today cycads are few and there is a need for Department of Agriculture Conservation and Environment to conserve few cycads that are available as they do not grow anywhere around the world
Cycads are facing the threat of extinction due to over-utilization by people. People over use and destroy cycads by harvest the palnts and plough cycads in private gardens around the world because their leaves are very beautiful and attractive.

The aim of this article is to investigate the large number of cycads (Encephalartos transvenosus ) in the Modjadji nature reserve.

The Modjadji cycad is one of the largest cycads in South Africa. Encephalartos transvenosus is being protected in Modjadjie Nature Reserve which is found to the north of Tzaneen. People of Balobedu said Encephalartos transvenosus is "Modjadji's palm" and they named it after the Rain Queen. The Rain Queen or Modjadji is the queen of Balobedu . Queen modjadji is areal person and she is known by its power of making rain. Sometimes the Encephalartos plants are commonly called bread palms because the stem is used to make crude bread.

The people of Bolebedu are using these plants as a sacred and they also use it to receive the royal protection from their rain queen that is why they respect these plants. This species is threatened at Modjadji Nature Reserve. The Department of Water Affairs and Tourism (DWAF) plays an important role by conserving cycads plants available at modjadji nature reserve

One can say, cycads are similar to ferns or palms as they have large divided leaves. yes, they are, but not very closely – they’re still more related to palms than either is to us, for example, Cycads are similar to primitive seed plants because the motile sperm produced by living seed plants of cycads are similar to those produced by primitive seed (5).

E. transvenosus is a tree that can reach the height of approximately 6m (2). Cycads fall in the genus Encephalartos and the family Zamiaceae. The plant is not found in large numbers that they tend to grow in small groups. The species has numerous leaves that are arranged in a dense crown. The leaves that can spread up to 2.5 m. E. transvenosus are an evergreen plant. Cycads have large stout trunk and compound leaves. The leaves are light green with fine brown hairs wile the mature E. transvenosus has dark glossy green colour. Its leaves can spread up to 2,5m long. The E. transvenosus is a deciduous plant that produces golden brown cones during late summer. Its trunk can grow up to 45cm Diameter (2). E. transvenosus can survive approximately 100 years.

The species prefers to live in free frost area. It grows well in drained soil, light shade and full sun (4). The cones of E. transvenosus are destroyed by baboons as they occasionally break the immature cones. The seeds are eaten by beetles. The E. transvenosus play an important role in a diet of reptiles that are found in the Modjadji reserve. The management of modjadji reserve are trying to balance and protect this species from reserve. Many animals such as squirrels, monkeys, birds and baboons are attracted by the brightly colour of E. transvenosus. The species is easily propagated from seeds. The species need to conserves from their predators.

Indigenous tribes obtained starch from the stems of E. transvenosus and used it for food. They soaked and grinded the nuts of E. transvenosus in order to remove the nerve toxin although they do not remove the entire toxin from the plants which cause health problem to the people.

The mudjadfji nature reserve is found in the Bolobedu Mountains near Duiwelskloof harbours having some of the most fascinating plants in Southern Africa. One of these plants is E. transvenosus. E. transvenosus is endemic to Limpopo Province and Mpumalanga in South Africa. The reserve covers an area of 530 hectors. E. transvenosus is protected in the Letaba district that receives an annual rainfall of 1500mm (3). The region is a frost free area.

All Encephalartos species are endangered excluding the E. transvenosus because is protected at Modjadji Nature Reserve. Cycads decrease in number as people destroy their habitat. Conservation

The habitats of cycad are being destroyed in the entirety of the world. The forests were cleared for timber and for plant crops e.g. Mexico. In countries where cycads are endemic, plants are being destroyed for housing e.g. South Africa. Currently, there is an increase demand for cycads as the prices of cycads have increased. In South Africa Encephalartos species are selling for thousands of dollars Premium. A botanical garden can remove a cycad from modjadji cycads reserve for research purposes.

There are many people that want to conserve cycads in their own way. If we all work together, and do what is best for the cycads, cycad will no longer decrease in number.

References
1. Ken Hill, 2004. Introduction to Cycads.[Online].[Cited, 02 March 2007].Available from: http://plantnet.rbgsyd.nsw.gov.au/PlantNet/cycad/cycintro.html

2. Christopher J.2004. Encephalartos transvenosus [Online].[Cited, 27 February 2007]. Available from: http://www.conifers.org/za/en/transvenosus.htm

3 Winter J.2005. Encephalartos transvenosus Stapf & Burtt Davy [Online].[Cited, 26 February 2007]. Available from: http://www.plantzafrica.com/plantefg/encephtrans.htm

4. Wikipedia contributors. Cycads [Internet]. Wikipedia, The Free Encyclopedia; 2007 March 4, 13:16 UTC [Cited 2007 Feb 27].Available from: http://en.wikipedia.org/wiki/Cycad

5. David L. 2006 Cycads [Online].[Cited 04 March 2007]. Available from: http://www.nd.edu/~fboze/cycads.htm

Linette Netshiheni
CSIR Pretoria
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