Species

Olearia chathamica

Etymology

Olearia: Derived from the latinised name (Olearius) of the 17th century German botanist Adam Oelenschlager
chathamica: From the Chatham Islands

Current Conservation Status

2018 - Threatened - Nationally Vulnerable

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2012 - At Risk - Declining
2009 - At Risk - Declining
2004 - Range Restricted

Qualifiers

2012 - IE, PD
2009 - IE, PD

Authority

Olearia chathamica Kirk

Family

Asteraceae

Brief Description

Flat-topped small tree with narrow leathery saw-edged dark green leaves that are white underneath and large whiteish daisy-like heads inhabiting the Chatham Islands. Leaves 2.5-8cm long by 1.5-4cm wide, widest at middle, many even small thick teeth along edge. Flowers 3-4.5cm wide, petals white, centre purple.

Flora Category

Vascular - Native

NVS Species Code

OLECHA

The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

Structural Class

Dicotyledonous Trees & Shrubs

Synonyms

Olearia chathamica Kirk var. chathamica, Olearia chathamica var. dendyi Cockayne, Olearia oporina Hook.f.

Distribution

Endemic to the Chatham Islands where it is known from the southern tablelands, Pitt, Mangere and South-East Islands.

Habitat

A small tree of rocky spurs, steep coastal cliffs and scarps and open forest developed on deep peat, mostly on steep, rocky areas inaccessible to stock. Occasionally it is found in sphagnum bogs, lake shore scarps and valley flank tree lands.

Features

A small tree with a rounded canopy. Leathery pointed leaves with toothed edges, glossy upper surfaces and downy white undersides. It produces sprays of large daisy flowers with white rays and pale violet to deep purple centres. It flowers from October to March and fruits from November to April. Could be confused with Chatham aster (Olearia semidentata) from which it differs in its habitat preferences, taller, heavily branched tree-form, wider darker green leaves, and white flowers with deep purple discs.

Similar Taxa

Olearia semidentata

Flowering

October - March

Flower Colours

Violet / Purple,White

Fruiting

November - April

Threats

Threatened by fire and domestic and feral browsers (sheep, cattle, pigs and possums) and land clearance for farming. Forest degradation on the southern tablelands, as a consequence of unrestricted stock access, and feral animals also threatened this species. Recruitment failure over in many populations has resulted in moribund stands verging on the point of collapse. The species is now secure only on cliffs east of Rangaika, parts of Pitt, Mangere and South East islands.

Chromosome No.

2n = 108

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Where To Buy

Not commercially available.

      

Attribution

Fact Sheet prepared for NZPCN by P.J. de Lange 1 August 2003.

References and further reading

Walls, G.; Baird, A.; de Lange, P.J.; Sawyer, J.W.D. 2002: Threatened plants of the Chatham Islands. Wellington, Department of Conservation.

This page last updated on 7 May 2014