Common Name: Clanwilliam Cedar

General Information

Widdringtonia cedarbergensis is an evergreen shrub or small tree that can grow up to 20 metres tall though it is more typically within the range 5 - 7 metres. The reddish-grey bark is thin and fibrous, soon flaking; the trunk becomes massive and gnarled with age, around 90 - 200cm in diameter (trees 300cm in diameter used to be known); the crown is initially conical, later becoming rather broad and open[, , ]
The plant was at one time very heavily exploiitted for its valuable wood and medicinal resin, but over-exploitation has led to this tree becoming very rare in the wild[]. It is recommended for cultivation as an ornamental in South Africa, andt is also used as a Christmas tree there[]
Intensive exploitation of Widdringtonia cedarbergensis in the past, accompanied by changes in intensity and frequency of fires, has resulted in an estimated and observed decline in area of occupancy and quality of habitat of more than 80%. The causes of this decline, while understood, are not reversible and have not ceased. The plant is classified as 'Critically Endangered' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

This tree can be a fire hazard in areas subject to regular natural fires. Due to its high resin content the tree burns incredibly fast, and has even been known to explode![]

Botanical References

Range

Southern Africa - S. Africa (Western Cape)

Habitat

Rocky outcrops on mist-cloaked mountains and cliffs; at elevations from 915 - 1,980 metres[, ].

Properties

Conservation Status	Critically Endangered
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	6.00 m
Growth Rate	Slow
Cultivation Status	Ornamental, Wild

Cultivation Details

Widdringtonia cedarbergensis is native to the semi-arid, mediterranean climate of S. Africa with hot, dry summers and cool to cold, moist to wet winters. The mean annual rainfall is within the range 500 - 1,000 mm. The plant experiences regular summer droughts and, especially at the higher limits of its range, winter snow and frosts[]. Although the plants are frost hardy in their native range, they are probably not hardy to prolonged cold at temperatures below -5°c, especially in moister climates[, ].
In its natural environment the plant can tolerate shallow, infertile soils and severe droughts[]. It requires a very well-drained soil and excessive wetness should be avoided at all times[].
Plants are not difficult to grow as potted specimens, though watering should be carried out with care, especially in summer when it is very easy to overwater[].
The wood is fragrant[].
Pollen analysis and historical records suggest that the species’ range was significantly larger in the past, but the main stands of it were ruthlessly exploited for their timber by European settlers in the Cape, and few mature trees now remain. Re-establishment is proving to be very slow and difficult, with plants facing various threats, including seed predation by birds and rodents, grazing of seedlings, low seed yields and illegal timber extraction; fire, however, remains the chief concern. Due to their high resin content cedars burn incredibly fast, and can even explode! Yet fire is essential for seed release and seedling establishment[121. Rigorous management of the Cederberg area, with routine, controlled burning, may be the only way to save this species, and attempts are ongoing[].
Female cones develop in the autumn, and remain on the tree for almost 3 years before the seeds are released during late summer[].

Edible Uses

None known

Medicinal

A clear, hard gum yielded by the cones and branches has been used medicinally in the form of fumigations in the treatment of gout, rheumatism or oedematous swellings[].
The gum has been used for making plasters[].

Other Uses

The gum has been used for making a varnish[].

The wood is beautiful, light yellow to whitish, resinous and fragrant, dense and exceedingly durable. It works well, takes a fine polish and is borer-proof[]. It is excellent for making furniture (the pews, doors and carved altar in the Anglican Church and the furnishings in the Courthouse in Clanwilliam are both made of Clanwilliam cedar), it was also popular for shipbuilding and was used for almost all the woodwork needed by the early European settlers in the region. It is very durable and was once sold by the wagonload for telegraph poles and fence posts - it has been claimed that the posts had not decayed by more than the thickness of a sheet of paper after 30 years in the ground, and that they were still immovable 100 years later[, ].

Propagation

Seed - germinates easily and well without any pre-treatment[]. Sow in a well-drained, sandy soil. Germination takes 3 - 4 weeks and seedlings can be transplanted as soon as they are large enough to handle. Initial growth is good, and saplings are best grown on in semi-shade until large enough to plant out[].