Eucalyptus delegatensis R.T.Baker subsp. delegatensis

alpine ash, gum-topped stringybark, white-top

Australia: Victoria and New South Wales.

In New Zealand cultivated in timber plantations, and occasionally in tree collections and for amenity uses; occasional naturalisation from nearby planted specimens.

Scattered records from throughout New Zealand, particularly from the central North Island and from the South Island. It is more cold-tolerant than many of the other eucalypts and more likely to be grown in cooler regions.

• A tree to 50 m or more tall, rough bark often furrowed, stringy or fibrous, grey to black on lower part of trunk (half-barked); smooth bark on upper trunk and branches is white, cream, yellow, grey or grey-green, occasionally with ribbons of shedding bark in the upper branches; branchlets may or may not be waxy grey-white.
• Adult leaves glossy, green to blue-green, same colour above and below, alternate, stalked, lanceolate to sickle-shaped, to 230 mm long and 55 mm wide, usually the two sides of the leaf base meeting at different points on the midrib (oblique) or tapering to the stalk, side-veins at an acute angle to midrib.
• Juvenile leaves opposite, short-stalked for 4 or 5 nodes, becoming alternate, and broadly lanceolate to ovate or sickle-shaped, to 200 mm long and 82 mm wide, blue-green, hanging downward.
• Flowers in stalked clusters of 7 to 15 or more, in leaf axils, stalk of cluster angular, to 20 mm long, mature buds stalked, bud stalks to 9 mm long. Mature buds club-shaped, to 5 mm long and 4 mm wide, green to yellow to red; bud cap conical to rounded with a small pointed tip, flowers white.
• Fruit a stalked woody capsule, stalks to 6 mm long, barrel-shaped or rounded, usually to 11 mm long, to 11 mm wide, rarely waxy grey-white, disc level or descending inside the capsule rim, valves usually 3 or 4, near rim level or enclosed within the capsule.

Tree to 50 m or more tall.

Bark rough on lower part of trunk, often furrowed, stringy or fibrous, grey to black, sometimes with horizontal black scars; smooth bark on upper trunk and branches, white, cream, yellow, grey or grey-green, occasionally with ribbons of shedding bark in the upper branches, branchlets may or may not be waxy grey-white. Hairs and adventitious roots absent. Young stem rounded in cross-section, sometimes waxy grey-white.

Adult leaves alternate, stalked, lanceolate to sickle-shaped, 75–230 mm long, 13–55 mm wide, usually the two sides of the leaf base meeting at different points on the midrib (oblique), or tapering to the stalk, same colour above and below, glossy, green to blue-green, side-veins at an acute angle to midrib, vein reticulation sparse to moderate, intramarginal vein parallel to and well removed from margin, oil glands present; leaf stalk 10–45 mm long.

Juvenile leaves opposite, short-stalked for 4 or 5 nodes becoming alternate, stalked, broadly lanceolate to ovate or sickle-shaped, 70–200 mm long, 27–82 mm wide, blue-green, hanging downward.

Flowers in stalked clusters of 7 to 15 or more, in leaf axils, stalk of cluster angular, 8–20 mm long; mature buds free, stalked, bud stalks 3–5(–9) mm long, buds club-shaped, sometimes broadly, 4–5 mm long, 4 mm wide, green to yellow to red; bud cap conical to rounded with a small pointed tip, flowers (stamens) white; in mature open flowers, petals and sepals absent. Main flowering period: summer to early autumn.

Capsules woody, stalked, stalks 2–6 mm long, barrel-shaped or rounded, 6–11(–19) mm long, 6–11 mm wide, rarely waxy grey-white, disc level or descending inside the capsule rim, valves 3 or 4(–5), near rim level or enclosed within the capsule.

Eucalyptus fraxinoides, E. delegatensis and E. pauciflora are blue-leaved ash eucalypts (referring to the colour of the juvenile leaves). Eucalyptus fraxinoides and E. delegatensis both have rough bark on the lower part of the trunk, but the bark of E. fraxinoides is compact, whereas the bark of E. delegatensis is fibrous. Eucalyptus pauciflora has smooth bark over the whole trunk and differs from all other ash eucalypts by the parallel side veins of the adult leaves. All three species can sometimes have some waxy grey-white (glaucous) parts, such as branchlets or young stems, buds, capsules or juvenile leaves, a feature unlikely to occur in other ash eucalypts.

Eucalyptus delegatensis is listed as a DOC Environmental Weed in New Zealand.

There is a second subspecies, E. delegatensis subsp. tasmaniensis (Tasmanian oak), that is indigenous to Tasmania, and there are records of old plantations of this subspecies in New Zealand. It has rough bark over the whole trunk and has smaller, rounder juvenile leaves to about 70 mm long.

Eucalyptus is a genus of nearly 800 species, most of which are endemic to Australia, with a few species extending to parts of Malesia and as far north as the Philippines.

• EUCLID
• Flora of Australia
• Flora of New Zealand Online (species profile)
• Flora of New Zealand Online (weed profile)
• GBIF
• iNaturalist NZ
• NZPCN
• PlantNET: New South Wales Flora Online
• Plants of South Eastern New South Wales
• VicFlora: Flora of Victoria