Carmichaelia juncea
Common names
a native broom
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Trees & Shrubs - Dicotyledons
Simplified description
Rare sprawling leafless brownish shrub inhabiting gravel flats. Twigs flattened, 1.5-2mm wide, grooved, lying flat along ground. Flowers small, pea-like, white or with purple streaks. Fruit a very small dry pod containing up to 6 very small mottled seeds and which does not split open.
Flower colours
Violet/Purple, White
Detailed description
Prostrate, sprawling, virtually leafless, shrub forming flat dull grey-green, yellow-green to very dark green mats up to 0.2 x 1.5 m. Branches up to 0.8 m, completely flat, rarely ascending. Cladodes linear, striate, compressed, green, grey-green, yellow-green to light brown, sparsely hairy, prostrate, 55-160 x 1.5-2 mm; apex subacute. Leaf nodes 8-15. Leaves 1-3(-5)-foliolate, somewhat fleshy; upper surface mottled brown, brown-green or green; undersides green; apex emarginated or retuse, base cuneate to obtuse, lamina margin sparsely hairy or glabrous. Terminal leaflet 5.5-14 x 2-4 mm, oblong, lateral leaflets 3-5 x 1-2.5 mm, obovate. Leaves on cladodes reduced to a triangular scale < 1 mm long. Stipules free, 0.5-0.8 x 1mm, broad-triangular, initially herbaceous, drying membraceous. Inflorescence a raceme, 1(-2) per node, bearing 4-6 flowers. Peduncle 2-4 mm long, hairy, green. Pedicel 1-1.5 mm, hairy, pale green flushed with red. Calyx 1.5 x 1.25 mm, campanulate, green, glabrous. Calyx lobes 0.1 mm long, broad-triangular to triangular. Bud pale green. Standard 4-5 x 4-5 mm, obovate, erect; distal and central portions of undersides purple, margins and proximal areas white or purple-veined,; distal and central areas of upper surface white, proximal portion green or purple-veined; apex retuse, margins recurved; claw, c.1.5 mm long, pale green. Wings 3.5-4 x 1-1.5 mm, oblong, longer than keel, both surfaces white, sometimes purple-veined; claw 1-1.5 mm long, pale green. Keel 4.5 x 1.5 mm; distal area purple, white or purple-veined in central and proximal areas; claw 1.5-2 mm, pale green. Stamens 3.5 mm long. Pistil of similar length. Style with a ring of hairs below stigma. Pod, persistent, 3.5-6 x 1.75-2 mm, oblong, valves inflated, yellow-grey, dark grey, dark grey-black, usually indehiscent; beak 0.25-0.5 mm, slightly curved, stout, pungent. Seeds (1-)4(-6) per pod, 1.25-1.5 x 1 mm, oblong-reniform, brick red, orange, olive green, or green-yellow, usually mottled with black.
Similar taxa
Carmichaelia juncea is somewhat similar to Carmichaelia compacta Petrie and C. curta Petrie but is easily distinguished from these species by its sprawling, prostrate growth habit and rather slender, wiry branchlets.
Distribution
Endemic. North and South Islands. In the North Island it was collected once in the 1840s from the Ngaruroro River, and has not been seen since. In the South Island it was formerly known from North West Nelson, Marlborough, Canterbury, Westland, Otago and Southland. It is now only known from a small area near Puponga in North West Nelson, and in scattered sites from Franz Josef Glacier south to near Haast.
Habitat
Occurs on stable but unconsolidated river bed gravels and stony, sandy and grassy edges of lakes, where competition from other plants is limited, or in coastal shrubland and turfland on weathered conglomerate rock.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Threatened – Nationally Vulnerable | Qualifiers: DPS, DPT, EF, PF
Threats
An apparently biologically sparse species, it is now extinct over much of its former range. Now presumed extinct in the North Island. Its near loss from the South Island can be attributed to its natural rarity, thereby increasing its vulnerablity to over-collection. The flat creeping habit and requirement for open ground, means it is highly vulnerable to weed competition. It is browsed by rabbits, possums, and livestock.
Detailed taxonomy
Family
Synonyms
Carmichaelia prona Kirk, C. fieldii Cockayne, C. lacustris G.Simpson, C. nigrans G.Simpson var. nigrans, C. nigrans var. tenuis G.Simpson, C. floribunda G.Simpson
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
October - January
Fruiting
November - March
Life cycle and dispersal
Seeds are possibly dispersed by wind and granivory (Thorsen et al., 2009).
Propagation technique
Easy from seed or semi-hardwood cuttings. Interesting plant for rock-gardens, and tolerant of exposed, dry conditions. Prefers free-draining soils, in full sun. An excellent pot plant. Like many South Island Carmichaelia, it does better in drier, less humid climates.
Other information
Plant of the Month
This plant has been featured as a Plant of the Month – see Trilepidea: NZPCN newsletter for July 2018 for the full story.
Etymology
carmichaelia: After Carmichael, a botanist
juncea: Rush-like
NVS code
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.
CARJUN
Chromosome number
2n = 32
Previous conservation statuses
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2017 | Threatened – Nationally Vulnerable | Qualifiers: CD, DP, EF
2012 | Threatened – Nationally Vulnerable | Qualifiers: CD, EF, RF
2009 | Threatened – Nationally Vulnerable | Qualifiers: CD, EF, RF
2004 | Threatened – Nationally Endangered
Regional conservation statuses
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | Regionally Extirpated | Qualifiers: HR, TL
Referencing and citations
References and further reading
Heenan, P. B. 1995: A taxonomic revision of Carmichaelia (Fabaceae - Galegeae) in New Zealand (Part I). New Zealand Journal of Botany 33: 455–75.
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(4): 285-309.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange (30 November 2005). Description modified from Heenan (1995).
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Carmichaelia juncea Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/carmichaelia-juncea/ (Date website was queried)