Ozothamnus
Credits
Article from Bean's Trees and Shrubs Hardy in the British Isles
Recommended citation
'Ozothamnus' from the website Trees and Shrubs Online (treesandshrubsonline.
Family
- Asteraceae
Synonyms
- Faustula Cass.
- Petalolepis Less.
- Swammerdamia DC.
Editorial Note
Bean treated only the New Zealand species of Ozothamnus, among which were four New Zealand members of the (now exclusively Australian) genus Cassinia that have since been referred to Ozothamnus leptophyllus. This group - Cassinia fulvida, C. leptophylla, C. retorta and C. vauvilliersii var. albida - was described as ‘very much alike in general appearance, and [ ] not easily distinguished on paper.’ (Bean included C. vauvilliersii with this group, though this has been referred to a separate species, Ozothamnus vauvilliersii.) The species in this group were described as having ‘a certain resemblance to the heaths in habit and in their small, crowded, narrow leaves, but bear[ing] their numerous tiny flowers (or rather flower-heads) in flattish terminal clusters. Such beauty as the flower-heads possess is given by the white, recurved tips of the inner bracts’ (Bean 1976).
The text below has been adapted to reflect updated taxonomy, as have the descriptions of individual species.
A genus of about fifty species of evergreen shrubs or weakly woody perennial herbs, confined to the Australasian region. Leaves alternate, often heath-like. Flower-heads resembling those of Helichrysum, usually small, often in dense corymbs. Involucral bracts with dry papery appendages, often conspicuously radiating and simulating the ligules of ray-florets, then usually white; usually a few outer florets female, the rest bisexual, all discoid (ray-florets nil); receptacle without scales. Closely related to Cassinia (from which it differs by the absence of receptacular scales) and Helichrysum, from which no one technical character serves to distinguish it, and in which it is often included as a subgenus.
There is no monographic treatment of the genus, and its taxonomic status is still in need of clarification. The Australian species may be identified by reference to: N. T. Burbidge, ‘A Monographic Study of Helichrysum subgenus Ozothamnus’, in Austr. Journ. Bot., Vol. 6, pp. 229–84 (1958); and those of New Zealand to: H. H. Allan, Flora of New Zealand, Vol. 1, pp. 715–21 (1961).
Footnotes
Revised by C. Jeffrey of the Herbarium, Royal Botanic Gardens, Kew.