The New Zealand Plant Conservation Network

Species

Cenchrus caliculatus

Etymology

Cenchrus: From the Greek cenchros which means millet
caliculatus: From the Greek kalux (in Latin calyx) 'case of a bud' or 'husk', meaning to have a calyculus or epicalyx (whorls or bracts below the calyx)

Common Name(s)

Large Burr Grass, Devil Grass, Owee Grass

Current Conservation Status

2012 - At Risk - Naturally Uncommon

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 - At Risk - Naturally Uncommon
2004 - Range Restricted

Qualifiers

2012 - RR, TO
2009 - TO, OL

Authority

Cenchrus caliculatus Cav.

Family

Poaceae

Flora Category

Vascular - Native

NVS Species Code

CENCAL

Structural Class

Grasses

Synonyms

Cenchrus calyculatus Cav. is an orthographic variant

Distribution

Indigenous. In New Zealand known from Raoul Island (Kermadec Islands group) only. Formerly widespread across the Pacific, now very rare or extinct thtroughout most of its former range

Habitat

Strictly coastal. In New Zealand known only from rocky bluffs, associated talus and from beach sands in one small part of Raoul Island. Elsewhere in the Pacific it has been recorded growing on basalt rock exposures both inland and on the coast, on calcarenite, uplifted coral and coral sand.

Features

Robust, through somewhat lax, spreading, clump-forming grass arising from a stout, woody rhizome; culms trailing and rooting freely from lower nodes. Branching initially extravaginal becoming intravaginal. Leaf-sheath longer than internodes, firm papery, keeled, smooth, minutely scabrid on narrow membranous margin and on ribs below collar. Ligule 1.0-1.5 mm, truncate with a densely ciliate rim. Leaf-bade 70-200 x 4-9 mm, linear-lanceolate, rounded-truncate at base, flat, firm, undersides smooth, upper surface minutely scabrid on ribs; margins somewhat thickened, minutely scabrid, tapering to a long acuminate apex. Culm 700 x 2-2.5 mm diameter, terete, more or less angled, internodes minutely pubescent-scabrid on ridges below panicle. Panicle 100-250 x 15 mm, spicate; rachis triangular, slightly winged, densely minutely pubescent-scabrid, bearing ovoid clusters of 1-3 spikelets, hidden amongst bristles and densely, spirally arranged along rachis; clusters 7-10 x 4-7 mm, including involucre of stiff bristles, at first appressed, finally borne at right angles to rachis; bristles retrorsely barbed, very variable in length, 0.5-11.0 mm, outermost smaller, terete, inner more planoconvex with margins densely softly long-ciliate, one bristle in each cluster usually exceeding the others, Spikelets 5-6 mm, 2-flowered, < inner bristles, sessile, glabrous, light green to almost colourless. Glumes hyaline; lower 2-4.5 mm, 1-nerved, upper 4-5 mm, 5-nerved. Lower floret with lemma 4.8-6.0 mm, 5-nerved, scabrid; palea keels ciliate, interkeel minutely hairy, margins scabrid; anthers 1.5-2.0 mm, brown with thick orange-yellow filaments. Upper floret with lemma 5.0-5.5 mm, 5-nerved, finely scabrid-papillose; palea finely scabrid-papillose; anthers as in lower floret. Seed 2.2-2.7 mm, more or less ellipsoid.

Similar Taxa

In New Zealand none. Cenchrus caliculatus is a very robust species within the genus. In the Pacific it appears to have declined in favour of the widespread, weed C. echinatus L. That species is very much smaller, and has dark maroon-red to purple inflorescences. It is not closely related to C. caliculatus, and has yet to be found in New Zealand.

Flowering

November - May

Fruiting

December - September

Propagation Technique

Easy from fresh seed, rooted pieces and node cuttings. very cold sensitive.

Threats

Unclear. This very large grass has declined markedly over the last 40 years, and is now extinct or scarce over large parts of former range. No one is exactly sure why (W. R. Sykes pers. comm.).

Chromosome No.

2n = 102

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Spiny florets are spread by attachment and possibly wind (Thorsen et al., 2009).

This page last updated on 25 Aug 2015