Scientific Name:
Carmichaelia arborea (G.Forst.) Druce, Bot. Soc. Exch. Club Brit. Isles 4 Suppl.: 612 (1917)
  • Lotus arboreus G.Forst., Fl. Ins. Austr. 52 (1786)
  • = Carmichaelia australis var. γ grandiflora Hook.f., Bot. Antarct. Voy. II. (Fl. Nov.-Zel.) Part I, 50 (1852)
  • Carmichaelia grandiflora (Hook.f.) Hook.f., Handb. New Zealand Fl. 49 (1864)
  • = Carmichaelia grandiflora var. alba Kirk, Stud. Fl. New Zealand 111 (1899)
  • = Carmichaelia grandiflora var. dumosa Kirk, Stud. Fl. New Zealand 111 (1899)
Vernacular Name(s):
South Island broom; Swamp broom; Tree broom

Shrub, up to 2 m × 2 m; sometimes suckering and forming broad patches up to 1 m tall. Branches up to 80 mm diameter, stout, ascending and spreading. Cladodes 70-150 × 1.5- 3 mm, erect to spreading, sometimes drooping, rarely divaricate, linear, striate, compressed, green to dark green, sometimes hairy when young, glabrous when mature, apex obtuse; leaf nodes 4—11. Leaves 1—3(—5)-foliolate, present on seedlings and on adult plants, terminal leaflet larger; lamina 2-7 × 1-4.5 mm, obovate, broad-obovate to broad-elliptic, fleshy, green, adaxial surface glabrous, abaxial surface glabrous or with a few scattered hairs, apex emarginate, base cuneate; petiole 7—11 mm long, glabrous except for a tuft of hairs at petiolule base, green; petiolule < 0.5 mm long, glabrous, light green. Leaves on cladodes reduced to scales, < 0.8 mm long, broad-triangular, glabrous, apex subacute. Stipules 0.9—1.3 × 1—1.4 mm, free, triangular, glabrous, apex subacute with a tuft of hairs, margin hairy. Inflorescence a raceme, 1 per node, each with 5—9(— 10) flowers clustered on upper third of raceme. Peduncle c. 8 mm long, glabrous, green. Bracts < 1 mm long, triangular, pale brown, adaxial surface hairy, abaxial surface glabrous, apex acute to subacute, margin hairy. Pedicel 1-1.5 mm long, glabrous, green. Bracteoles < 0.5 mm long, on upper part of pedicel or on receptacle, pale brown, adaxial surface hairy, abaxial surface glabrous, apex subacute to obtuse and with tuft of hairs. Calyx 3—3.5 × 2— 2.5 mm, campanulate, green, outer surface glabrous. Calyx lobes 0.5—1 mm long, triangular, inner surface hairy, appressed to corolla, apex acute. Standard 6— 6.5 × 7-8 mm, broad-obovate, patent, positioned towards front of keel, keeled, apex retuse or obtuse with an apiculate tip; white or with a pale central blotch, veins sometimes weakly flushed red-purple; claw c. 1 mm long, pale green. Wings 6-7 × 1.5- 2 mm, oblong, longer than keel, white, apex obtuse; auricle 0.2-0.3 mm long, triangular; claw 1.8-2 mm long, pale green. Keel (Fig. 2E) 5—6 × 1.5—1.8 mm, white, apex obtuse; auricle 0.3-0.5 mm long, triangular, white; claw 2-2.5 mm long, pale green. Stamens 4.5—5 mm long; dorsal filaments connate for c. ¾ of length, outer stamens free for c. 0.8 mm. Pistil 5-6 mm long, exserted beyond stamens, glabrous; ovules 8—9(—11); stigma with a ring of hairs at base. Pods 7—15 × 2.7-4.5 mm, oblong or broad-oblong, laterally compressed, erect, light grey or pale brown, both valves dehiscent at distal end; beak 2—2.5 mm long, in a central apical position, stout, pungenttipped. Seeds 2-3.7 × 1.6-2.4 mm, broad-oblong to broad-elliptic, 1-3 per pod, surface with 1—3 ridges, testa thin and membranous, light brown or tan. FL Dec-Mar, FT Jan—Dec.

[Reproduced from Heenan (1996, New Zealand J. Bot. 34: 157–177) with permission from The Royal Society of New Zealand.]

Indigenous (Endemic)
de Lange, P.J.; Rolfe, J.R.; Barkla J.W.; Courtney, S.P.; Champion, P.D.; Perrie, L.R.; Beadel, S.N.; Ford, K.A.; Breitwieser, I.; Schönberger, I.; Hindmarsh-Walls, R.; Heenan, P.B.; Ladley, K. 2018: Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series. No. 22. [Not Threatened]
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. [Not Threatened]
Druce, G. C. 1917 ("1916"): Nomenclatural Notes: Chiefly African and Australian. Report / Botanical Society and Exchange Club of the British Isles for 1916, 4 Suppl.: 601–653.
Forster, J.G.A. 1786: Florulae Insularum Australium Prodromus. Dietrich, Göttingen.
Heenan, P.B. 1995: Typification of names in Carmichaelia, Chordospartium, Corallospartium, and Notospartium (Fabaceae - Galegeae) from New Zealand. New Zealand Journal of Botany 33: 439–454.
Heenan, P.B. 1996: A taxonomic revision of Carmichaelia (Fabaceae-Galegeae) in New Zealand. Part 2. New Zealand Journal of Botany 34(2): 157–177.
Hooker, J.D. 1852–1853 ("1853"): The Botany of the Antarctic Voyage of H.M. Discovery Ships Erebus and Terror in the Years 1839–1843, under the command of Captain Sir James Clark Ross. II. Flora Novae-Zelandiae. Part I. Flowering plants. Lovell Reeve, London.
Hooker, J.D. 1864: Handbook of the New Zealand Flora: a systematic description of the native plants of New Zealand and the Chatham, Kermadec's, Lord Auckland's, Campbell's and Macquarie's Islands. Part I. Reeve, London.
Kirk,T. 1899: The Students' Flora of New Zealand and the Outlying Islands. Government Printer, Wellington, N.Z.