Species

Lepidium kirkii

Etymology

Lepidium: scale-shaped (pods)
kirkii: after Thomas Kirk (18 January 1828 - 8 March 1898), a NZ botanist and lecturer in natural sciences and regarded as a leader of botanical enquiry in NZ for over three decades. One of his most significant publications was Forest flora of NZ (1889) but he also contributed over 130 papers to the Transactions and Proceedings of the NZ Institute and other journals.

Common Name(s)

Kirk's scurvy grass, salt pan cress

Current Conservation Status

2012 - Threatened - Nationally Critical

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

2009 - Threatened - Nationally Critical
2004 - Threatened - Nationally Endangered

Qualifiers

2012 - CD, EF
2009 - CD, EF

Authority

Lepidium kirkii Petrie

Family

Brassicaceae

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

None

Distribution

Endemic. South Island. Central Otago, formerly probably widespread on saline/sodic soils from the Ida Valley and Maniototo Plains (Gimmberburn District) south to Alexandra in the Manuherikia Valley. Now known from 12 populations mainly centred on Galloway and Springvale area.

Habitat

Only known to occur on patches of saline/sodic soils (sometimes referred to as salt pans) in the semi-arid region of Central Otago. This habitat varies from highly weathered bedrock schist (e.g., Galloway) to the gravels and silts of old terrace surfaces (e.g. Patearoa), and usually supports few, if any, other plant species.

Features

A summer-green annual to short-lived perennial herb with slender, prostrate, thread-like, flexuous, glabrous, branching stems up to 100 mm long arising from a stout rootstock. Leaves entire, glabrous or sparsely hairy on margins. Basal leaves 5-30 x 0.3-0.6 mm, dark green to brown-green (almost black), linear, linear-spathulate, with persistent, broad sheathing scarious bases. Stem leaves 1-3 x 0.3-0.5 mm, brown-green, linear, linear-filiform to linear-oblanceolate. Racemes flexuous, 10-30 mm long; pedicels spreading, 1-2 mm at fruiting. Sepals 0.5-1 x 0.3-0.8 mm. Petals often absent, if present white narrow-spathulate about length of sepals. Stamens 4. Silicle 1.5-2 x 1-1.5 mm, ovate, valves glabrous; style 0.1 mm, free from narrow wing, slightly exceeding the shallow notch. Seeds 1.5 mm, ovoid, pale brown.

Similar Taxa

None

Flowering

November - March

Flower Colours

White

Fruiting

November - May

Propagation Technique

Easy from fresh seed. A short-lived species best treated as an annual. It not a particularly attractive plant and is unlikely to be popular in cultivation.

Threats

Habitat destruction resulting from cultivation, irrigation and weed invasion (particularly Plantago coronopus, and the grasses Lolium perenne and Poa pratensis) of the minute remaining fragments are probably the main reason for its rarity and the greatest threat to its survival. Many populations are infected with Albugo fungus which kills some plants (particularly seedlings) and can reduce the reproductive output of infected adult plants.

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Mucilaginous seeds are dispersed by attachment and possibly wind and water (Thorsen et al., 2009).

Where To Buy

Not commercially available

Notes

Lepidium kirkii is one of the very few salt pan endemics. It is an unusual species within the New Zealand members of the genus and is not closely related to the other species.

Attribution

Description adapted from Webb et al. (1988).

References and further reading

Allan, H.H. 1961: Flora of New Zealand. Volume I. Indigenous Tracheophyta: Psilopsida, Lycopsida, Filicopsida, Gymnospermae, Dicotyledones.Wellington, Government Printer.

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

Webb, C.J.; Sykes, W.R.; Garnock-Jones, P.J. 1988. Flora of New Zealand. Volume IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. Botany Division, D.S.I.R, Christchurch, New Zealand.

This page last updated on 3 Jun 2015