Angophora costata (Gaertn.) Britten

rusty gum, smooth-barked angophora, smooth-barked apple, Sydney red gum

Australia: New South Wales, central coastal Victoria.

In New Zealand cultivated as a landscape tree of parks and gardens; occasionally naturalised from nearby planted specimens.

Scattered records from the North Island and northern South Island of New Zealand.

• With distinctive smooth, orange or pink trunk when bark has been newly shed, fading to light grey in winter.
• Leaves opposite (as opposed to alternate in Eucalyptus) and tapered to a narrow tip.
• Petals white with a green keel, clawed.
• Fruit with prominent ribs.

Tree, growing to 30 m tall.

Main stems smooth-barked, bark orange to pink when young, ribbons absent, adventitious roots absent. Young stems rounded, without hairs.

Mature leaves in opposite pairs, lanceolate or sickle-shaped; 70–190 mm long, 12–35 mm wide, upper surface green or olive green, paler below; leaf blade flat, hairless and surfaces not puckered; margins entire; tips tapered to narrowly pointed; leaf stalks 9–25 mm long. Juvenile leaves ovate or elliptic; leaf stalks absent.

Flowers in terminal clusters, stalked; buds usually in 3s; petals 5, white, with a green keel, clawed (with narrow base); sepals 5, persistent; stamens white, longer than petals. Main flowering period: spring to summer.

Fruit dry, free, ribbed, 3–4-locular, 9–18(–20) mm long, 7–17(–20) mm wide.

Angophora species are closely related to the large Eucalyptus genus. Unlike Eucalyptus, all Angophora species have true petals and have opposite adult leaves. Angophora floribunda and A. hispida occur uncommonly in New Zealand, and neither has the smooth bark that is characteristic of A. costata. Angophora floribunda, commonly known as the rough-barked apple, is a large tree with fibrous bark and cream-white flowers; A. hispida, dwarf apple gum, is a small rough-barked, usually multiple-stemmed tree, with young stems and new foliage covered in red bristly hairs.

Two subspecies recognised, but apparently only A. costata subsp. costata is found in New Zealand. Angophora costata subsp. euryphylla possesses petals 5–8 mm long and a hairy calyx tube, whereas A. costata subsp. costata possesses petals 3–4 mm long and a usually hairless calyx tube.

Angophora is a genus of 10 species related to Eucalyptus and endemic to eastern Australia. Angophora costata is the only species that has smooth bark as well as the distinctly stalked adult leaves.

• Australia’s Flora: Growing Native Plants
• EUCLID
• Flora of Australia
• Flora of New Zealand Online
• GBIF
• iNaturalist NZ
• NZPCN
• PlantNET: New South Wales Flora Online
• Plants of South Eastern New South Wales
• VicFlora: Flora of Victoria