Natal giant cycad (Encephalartos natalensis)

KingdomPlantae
PhylumTracheophyta
ClassCycadopsida
OrderCycadales
FamilyZamiaceae
GenusEncephalartos (1)
SizeHeight: up to 6 m (2)

Classified as Near Threatened (NT) on the IUCN Red List (1) and listed on Appendix I of CITES (3).

Robust and tall, the Natal giant cycad is typically single-stemmed, but sometimes produces several trunks (2) (4). Like all cycads, the stem is mostly comprised of soft, pithy storage tissue protected by a solid layer of old leaf bases that give it a woody appearance (2) (5). The exceptionally long leaves are deep glossy green, and the male and female cones are golden-yellow (2) (6). Each plant bears up to five cones (2) (6), with the male and female reproductive organs never occurring on the same individual (5).

A South African endemic, the Natal giant cycad is widespread through southern Kwa-Zulu Natal, with outlying population in the Eastern Cape (1).

Usually occurs on rocky coasts and outcrops inland from the coast (1).

Cycads are long-lived, slow growing plants that always occur as individual male or female plants (2) (5). There is no way of determining the sex of a cycad until it begins to produce its first cone (5). For a long time cycads were thought, like cone-producing conifers, to be entirely wind pollinated (7). However, studies now suggest that the vast majority, if not all cycads, are actually pollinated by insects or more specifically weevils (2) (5) (7). To attract pollinators, male and female cones produce powerful odours, usually in the early morning or evening (5). Travelling between the sexes, the weevils pollinate the plants by inadvertently transferring pollen from the male cones to the receptive ovules of the female cones (5) (8).

The seeds produced by cycads are large and have a fleshy outer coat, but are relatively short-lived and vulnerable to desiccation. The fleshy outer layer is desirable to a range of animals such as birds, rodents and bats, depending on the species of cycad and region it occupies. However, with any luck the unpalatable seed is discarded some distance away from the parent plant in a hospitable environment in which to germinate (2).

Although the wild population is still fairly large (8,300 - 12,000 mature plants in 2003), the Natal giant cycad is thought to be undergoing a slow decline due to habitat loss, with some populations suffering as a direct result of bark removal for traditional medicine (9).

There are not known to be any specific conservation measures in place for the Natal giant cycad, but it is listed on Appendix I of CITES, which permits trade only under exceptional circumstances (3).

For further information on the conservation of cycads in South Africa see:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk

  1. IUCN Red List (October, 2009)
    http://www.iucnredlist.org/
  2. The Cycad Pages (October, 2009)
    http://plantnet.rbgsyd.nsw.gov.au/PlantNet/cycad/index.html
  3. CITES (October, 2009)
    http://www.cites.org
  4. Palm and Cycad Societies of Australia (PACSOA) (October, 2009)
    http://www.pacsoa.org.au/cycads/Encephalartos/princeps.html
  5. Whitelock, L.M. (2002) The Cycads. Timber Press, Portland, Oregon.
  6. Kirsten, K. (2001) Gardening with Keith Kirsten. Struik Publishers, Cape Town.
  7. Jolivet, P. (2005) Cycads and beetles: recent views on pollination. The Cycad Newsletter, 28: 3 - 7.
  8. Donaldson, J.S. (1997) Is there a floral parasite mutualism in cycad pollination? The pollination biology of Encephalartos villosus (Zamiaceae). American Journal of Botany, 84: 1398 - 1406.
  9. Donaldson, J.S. (2003) Cycads, status survey and conservation action plan. IUCN/SSC-Cycad Specialist Group. IUCN, Gland, Switzerland.