Metrosideros parkinsonii Buchanan

Parkinson’s rātā

New Zealand endemic.

Available from specialist native plant nurseries, but prone to dying in cultivation.

The most disjunctly distributed indigenous Metrosideros in New Zealand, known from the Great and Little Barrier Islands and then ± 550 km to the south-west, where it is confined to the western parts of Nelson and North Westland.

• Multi-trunked shrub or small tree.
• Aerial roots occasionally present.
• Adult leaves 25–75 mm long.
• Flowers not terminal, but directly on stems (cauliflorous), mostly below main vegetative branches.
• Flowers crimson.
• Calyx tube as wide as fruit.
• Fruit capsule ribbed.

Multi-trunked and many-branched shrubs or small trees up to ± 8 m.

Trunk occasionally with aerial roots. Bark pale grey to brown-grey, flaky. Branchlets 4-angled, hairless, initially red, spindly.

Leaves arranged in opposite pairs, each pair being at right angles to the pair below, leathery, 25–75 mm long, 15–30 mm wide, ovate-lanceolate, upper surface darkish green, paler below, leaf surface flat, not puckered, but often blistered or blemished red, upper and lower surfaces hairless, oil glands not readily visible on either surface; margins entire but slightly rolled under (revolute), tips mostly pointed rather abruptly; leaf stalks ± 2 mm long, stout, hairless.

Flowers in clusters of up to 8, borne mostly below main vegetative branches, directly on branches, cluster-branchlets often 3-flowered, or flowers solitary on cluster axis. Flowers ± 10–12 mm in diam., flower stalks 3–4 mm long, petals 5, ± 5 mm long, 5 mm wide, rounded, crimson, petal margins finely toothed; sepals 5, tips free, persistent, without hairs; stamens crimson, filaments 20–28 mm long, much longer than petals. Main flowering period: spring to early summer.

Fruit dry, ± 4–5 mm wide, 6–8 mm long, capsule ribbed, capsule dome occurring below the persistent calyx tube, calyx tube as wide as fruit, capsule splits along sides to release seeds.

The multi-trunked growth habit of the shrub or small tree coupled with spindly branches, shortly stalked, ovate-lanceolate leaves, and crimson flowers borne directly on branches uniquely identifies this species.

Metrosideros parkinsonii was given a conservation status of Threatened – Nationally Vulnerable in 2018 due the small area of occupancy and perceived risk from myrtle rust (caused by Austropuccinia psidii). At the time of writing there have yet to be reports of myrtle rust infecting this species.

Metrosideros is a genus of more than 50 species of trees, shrubs and vines, mostly found in the Pacific region. New Zealand is well represented by having 12 endemic species.

• Flora of New Zealand Online
• GBIF
• iNaturalist NZ
• NZPCN