Geum divergens
Common name
Geum, Avens
Synonyms
Oncostylus divergens (Cheeseman) F.Bolle
Family
Rosaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Structural class
Dicotyledonous Herbs other than Composites
Chromosome number
2n = 70
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2012 | At Risk – Naturally Uncommon | Qualifiers: RR
Previous conservation statuses
2009 | At Risk – Naturally Uncommon
2004 | Range Restricted
Distribution
Endemic. New Zealand: South Island, Hanmer Range (Miromiro, Mt Captain, Mt Charon)
Habitat
Subalpine to alpine (c.1300-1600 m a.s.l.). Colonising sandstone rock (crevices, ledges, shattered rock surfaces), fine colluvium, and erosion pavement in subalpine forest, scrub and tussock grassland.
Features
Short, stout herb up to 180 mm tall at flowering. Rhizome stout, woody, and creeping, clothed with long persistent, fibrous leaf base remnants. Leaves rugose, adaxially initially dull light green fading to yellowish-red, abaxially paler. Basal leaves numerous, up to 60 mm long, imparipinnate; lateral leaflets 2-4(-6) pairs, minute, terminal leaflet conspicuous, 20-35 mm long, orbicular-reniform, indistinctly lobed, coarsely crenate-dentate; margins densely ciliate with long white hairs, and minute pink hydathodes; adaxial surface otherwise sparsely villous, abaxial glabrescent to glabrous. Scapes up to 180 mm tall, slender, densely pubescent, hairs in mixtures of short and long eglandular hairs; bracts 2-5, up to 20 mm long, lanceolate, toothed, incised, rarely pinnate. Flowers 1-3(-5), up to 35 mm diameter. Calyx-lobes ovate-lanceolate, acute to acuminate, sometimes with minute bracteoles at the base, pubescent. Petals 12-15 mm long, white, obovate, obtuse. Disc green. Anthers yellow. Achenes pilose, gradually narrowed into a long glabrous, hooked style remnant.
Similar taxa
Allied to Geum uniflorum Buchanan with which it shares a strongly rhizomatous growth habit and large flowers. From that species it is distinguished by its larger overall dimensions, densely compact, leafy rosettes; leaves which are rugose, pale green above fading to yellowish red with age; dentate-crenate leaf margins which are densely fringed with white hairs and minute pink hydathodes; pubescent petioles and peduncles with intermixed long unicellular eglandular hairs; and 1-5 white flowers up to 35 mm diameter, with a central green eye and yellow anthers.
Flowering
November - December
Flower colours
Green, White
Fruiting
January - February
Life cycle
Pappate achenes are dispersed by wind (Thorsen et al., 2009).
Propagation technique
Easily grown in pots in an alpine house, and in cooler climates within a rock garden. Best grown from fresh seed.
Threats
Not Threatened - listed because it occupies a very small area within which it is very common.
Etymology
geum: Possibly from the Greek geuo ‘to give a pleasant flavour’, the roots of some species being aromatic.
divergens: From the Latin divergens, meaning divergent
Where To Buy
Not Commercially Available
Etymological notes
The name divergens refers to the flower colour of this species, which in the type is yellow, and so marked this species out from all of the other white-flowered New Zealand species. However all wild plants seen have white flowers, and it is now known that upon drying the white petals of all New Zealand Geum fade to yellow. As the type of Geum divergens was named 23 years after its collection it seems that during the time that elapsed between the initial collection and description the white petals of the specimen had faded to yellow. This, of course, caused considerable confusion with field botanists who were searching the Hanmer Range for an apparently unique yellow-flowered Geum for some 77 years! Description based on herbarium material.
Attribution
Fact Sheet Prepared by P.J. de Lange (1 August 2004). Description based on Allan (1961) and Cheeseman (1915)
References and further reading
Allan, H.H. 1961: Flora of New Zealand. Vol. I. Government Printer, Wellington.
Cheeseman, T. F. 1916: New species of plants. Transactions and Proceedings of the Royal Society of New Zealand 48: 210-215.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309
Citation
Please cite as: de Lange, P.J. (Year at time of access): Geum divergens Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/geum-divergens/ (Date website was queried)