Widdringtonia cedarbergensis

J.A. Marsh 1966

Common names

Clanwilliam cedar (English), Clanwilliam-seder (Afrikaans) or Cape cedar.

Taxonomic notes

Syn.: Callitris arborea Schrad. ex E.Mey. in Zwei Pflanzengeogr. Dokum. 73 (1843), nom. nud.

Description

Tree, 5-7 m tall but in protected places up to 20 m. Old trees are spreading, gnarled and massive. Bark is reddish grey, thin, fibrous and flaking. Juvenile leaves are up to 20 mm long and 2 mm wide; adult leaves are up to 4 mm long. Pollen cones are 1-2 mm long. Seed cones are globose, up to 25 mm diameter, bearing 4 dark brown woody scales with rough, warty faces. The tree may bear cones at various stages of development throughout the year. Seeds are ovoid, narrowly winged. It is very similar to W. schwarzii, but the native ranges are distinct (Palgrave 2002).

Distribution and Ecology

South Africa: Cape Province: in the Cedarberg Mountains (Farjon 1998), occurring singly or in scattered groups on rocky outcrops and mountain tops (Palgrave 2002).

Zone 9 (cold hardiness limit between -6.6°C and -1.1°C) (Bannister and Neuner 2001).

Remarkable Specimens

The oldest known living specimen, 356 years, was documented in a tree-ring chronology covering the period 1564-1976 (fully crossdated), collected by Peter Dunwiddie and Val LaMarche (doi.org/10.25921/gd67-6805).

Ethnobotany

The wood is beautiful, light yellow to whitish; it works well, takes a fine polish and is resistant to boring insects. The pews, doors and carved altar in the Anglican church and the appointments in the Courthouse, both in Clanwilliam, show this wood at its best. In past years this species was almost annihilated by woodcutters and veld fires, but today an active planting scheme is in progress (Palgrave 2002).

The species has seen exploratory use in dendrochronology; Dunwiddie and LaMarche (1980) developed a long chronology (413 years) based on trees growing on rocky and cliff sites.

Observations

No data as of 2023.11.06.

Remarks

The epithet recognizes the species' occurrence in the Cederberg Mountains.

Citations

Dunwiddie, Peter W. and Valmore C. LaMarche, Jr. 1980. A climatically responsive tree-ring record from Widdringtonia cedarbergensis, Cape Province, South Africa. Nature 286:796-797.

See also

The species account at Threatened Conifers of the World.

Botha, S.A. 1990. Seed-bank dynamics in the Clanwilliam cedar (Widdringtonia cedarbergensis) and the implications of beetle-triggered seed release for the survival of the species. South African Journal of Ecology 1: 53-59.

Farjon (2005) provides a detailed account, with illustrations.

Manders P.T., Botha S.A., Bond W.J. et al. 1990. The enigmatic Clanwilliam Cedar. Veld & Flora March 1990: 8-11.

Manders, P.T. 1987. A transition matrix model of the population dynamics of the Clanwilliam Cedar (Widdringtonia cedarbergensis) in natural stands subject to fire. Forest Ecology and Management 171-186.

Manders, P.T. 1987. Is there allelopathic self-inhibition of generative regeneration within Widdringtonia cedarbergensis stands?. South African Journal of Botany 53:408-4.

Meadows M.E. and Sugden J.M. 1989. Late Quaternary vegetation history of the Cederberg, South-western Cape. Palaeoecology of Africa and the Surrounding Islands 21: 269-2.

Midgley, J.J., Bond, W.J. and Geldenhuys, C.J. 1995. The Ecology of Southern African Conifers. In: Ecology of the Southern Conifers (eds N.J. Enright and R.S. Hill), pp. 64.

Mustart, P. 1993. What is the Cedarberg Without the Cedar? Veld & Flora 79(4): 114-117.

Pauw, C.A and Linder, H.P. 1997. Tropical African cedars (Widdringtonia, Cupressaceae): systematics, ecology and consevation status. Botanical Journal of the Linnean Society 123: 297.

Sugden J.M. and Meadows M.E. 1990. The history of the Clanwilliam Cedar (Widdringtonia cederbergenis): Evidence from pollen analysis. South African Forestry Journal 153: 64.

White, J. D. M., M. Stevens, J. Berndt, B. W. T. Coetzee, T. J. Massad, L. J. Nupen, D. Tye, and J. J. Midgley. 2020. Understanding recruitment limitations in a critically endangered species: The story of the iconic Cape cedar (Widdringtonia wallichii). Global Ecology and Conservation 23: e01062.