Euclid - Online edition

Eucalyptus viminalis subsp. viminalis


Click/tap on images to enlarge

Manna gum, Ribbon gum, White gum

Classification

Eucalyptus | Symphyomyrtus | Maidenaria | Euryotae | Viminales | Lanceolatae

Nomenclature
Eucalyptus viminalis Labill., Nov. Holl. Pl. 2: 12, t. 151 (1806) subsp. viminalis.

T: Van Diemen's Land, 1793, J.J.H. de Labillardière s.n.; holo: FI; iso: L.

Eucalyptus angustifolia Desf. ex Link, Enum. Pl. Hort. Berolinensis 2: 30 (1822). T.: n.v.

Eucalyptus viminalis var. rhynchocorys F.Muell. ex Maiden, Forest Fl. New South Wales 7: 131 (1820). T: Snowy R., Vic., F.Mueller s.n.; holo: MEL; iso: K, NSW.

[Eucalyptus pilularis auct. non Smith: A.P. de Candolle, Prodr. 3: 218 (1828).]
Description
Tree to 90 m tall. Forming a lignotuber.
Bark smooth over whole trunk or with a thick stocking of rough bark consistently to 2–6 m above base, fibrous, grey, brown or black; smooth bark often powdery, white to cream, yellow, light grey or pale brown, usually with conspicuous long ribbons of decorticated bark on upper trunk and in crown.
Juvenile growth (coppice or field seedlings to 50 cm): stem rounded or square in cross-section, smooth or warty; juvenile leaves opposite and sessile for many pairs, lanceolate to oblong to falcate, 2.5–9 cm long, 0.5–2 cm wide, base amplexicaul or rounded, green.
Adult leaves alternate, petiole 1–2.5 cm long; blade lanceolate to falcate, 8.5–23.2 cm long, 0.8–3 cm wide, flat or undulate, base tapering to petiole, concolorous, glossy or dull, green, side-veins greater than 45° to midrib, moderately to densely reticulate, intramarginal vein parallel to and close to margin or remote from it, oil glands mostly island.
Inflorescence axillary unbranched, peduncles 0.4–1 cm long, buds 3 per umbel, on pedicels to 0.5 cm long, or sessile. Mature buds ovoid to fusiform, 0.6–0.9 cm long, 0.3–0.6 cm wide, green to yellow, scar present, operculum conical to rounded or beaked, stamens irregularly flexed, anthers cuboid to oblong, versatile, dorsifixed, dehiscing by longitudinal slits (non-confluent), style long, stigma blunt or tapered, locules 3 or 4, the placentae each with 4 vertical ovule rows. Flowers white.
Fruit on pedicels to 0.3 cm long or sessile, cup-shaped or hemispherical, 0.3–0.7 cm long, 0.5–0.9(1.1) cm wide, disc raised-convex or oblique, valves 3 or 4, strongly exserted.
Seeds black, brown or grey, 1.2–3 mm long, ovoid or flattened-ovoid, often pointed at one end, lacunose, dorsal surface shallowly pitted, hilum ventral.

Cultivated seedlings (measured at ca node 10): cotyledons bilobed; stems rounded to square in cross-section, warty or smooth; leaves sessile, opposite for many nodes, lanceolate to falcate, 3.5–9.5 cm long, 0.8–2.5 cm wide, amplexicaul or base rounded, margin entire, apex pointed or rounded, discolorous, glossy, green above, paler beneath.
Flowering Time

Flowering has been recorded in January, February, March, April, May and December.

Notes

Eucalyptus viminalis is a species of small to very tall tree, widespread in well-watered parts of south-eastern Australia from southern Eyre Peninsula and Kangaroo Island of South Australia through Victoria, Tasmania and eastern New South Wales as far north as the tablelands between Inverell and Deepwater extending east to the escarpment. It is recognised most easily by the many pairs of opposite, sessile, lanceolate, green juvenile leaves. The crown is usually ribbony and the bark is mostly smooth in mountain forms although many populations elsewhere have a black butt or rough bark over most of the trunk. It is related to E. rubida and E. dalrympleana, both of which have rounded, not narrowly lanceolate juvenile leaves. Another seven-budded form, occurring on the Northern Tablelands of New South Wales and its eastern escarpment, has been described recently as E. nobilis (q.v.).

There are four subspecies:

E. viminalis subsp. viminalis
Occurs mostly in wetter or seasonally well-watered areas in New South Wales, Victoria, Tasmania, Bass Strait islands and South Australia, particularly in mountain valleys but also on alluvium along streams on tablelands areas. Subsp. viminalis can be very tall (to 90 m in Tasmania) and is generally smooth-barked and three-budded. In South Australia it occurs only in the central part of the Mt Lofty Ranges.

E. viminalis subsp. cygnetensis
Has rough bark usually to the larger limbs and "umbels of seven buds, infrequently less, to as few as three" (Boomsma, 1980, p. 295). Subsp. cygnetensis occurs from the Grampians in Victoria, south-west to Mt Gambier in South Australia, on Kangaroo Island, in the Port Lincoln area, and in the Mt Lofty Ranges where the rough-barked plants occur with mixtures of umbels in threes and sevens. Plants with 3s and 7s also occur in the Grampians.

E. viminalis subsp. hentyensis
Endemic to Tasmania where it grows on poor white sands on the west coast, north from Strahan. Subsp. hentyensis has little rough bark, coarse, broad juvenile leaves and buds in threes or sevens.

E. viminalis subsp. pryoriana
Subsp. pryoriana is endemic to Victoria and is a small tree of infertile coastal sands from south of Geelong to east of Marlo in Gippsland. It has rough bark over most of the trunk and buds in threes.

In 2011 Rule (see Muelleria 29(1) 5-7) described a new subspecies, Eucalyptus viminalis subsp. siliceana from Wail State Forest on the edge of the Wimmera region of Victoria. This subspecies has buds in umbels of 3s and 7s, buds with a rounded operculum, fruit within the size range of all other subspecies, and field juveniles with leaves narrowly lanceolate, opposite on the stem for many pairs but green to subglaucous with new growth tips glaucous. It occurs on siliceous sands. It is not (yet) included in EUCLID key.

Eucalyptus viminalis belongs in Eucalyptus subgenus Symphyomyrtus section Maidenaria, a large group of species more or less restricted to south-eastern Australia, characterised by bilobed cotyledons, simple axillary inflorescences, buds with two opercula, stamens with versatile anthers and flattened seeds with a ventral hilum. Within this section, E. viminalis belongs in series Viminales subseries Lanceolatae, having buds in threes or sevens, fruit with an ascending disc and exserted valves, and green, sessile, lanceolate juvenile leaves opposite for many pairs.

Origin of Name
Eucalyptus viminalis: Latin viminalis, bearing shoots or ribbons for wicker-work, presumably referring to the prominent ribboning of the bark.
Copyright © CANBR 2020, all rights reserved.