A tree capable of reaching a height of 50 metres, with a broad to narrow canopy spread – often weeping.
It has a wide natural geographic range – usually found in cooler or wetter habitats in New South Wales, south from near or just over the Queensland border, along the tablelands / and highlands of the coastal areas (with a disjunction between populations on the northern tablelands versus those on the central and southern tablelands) to Wombat State Forest and Great Otway National Park and ranges of South Gippsland in Victoria and into central Victoria. It also occurs in North-west Tasmania (south of Devonport) where it is restricted to the catchment of the Forth River.
It can be found on a range of soils – sandy to shale and basalt. It forms a dominant part of some described vegetation communities in NSW.
Bark is rough, finely fibrous or flaky grey (peppermint-bark) on the trunk and branches, usually smooth grey bark on branches thinner than 80 mm. The bark sheds off in small fibres when rubbed with the hand (a useful identification feature).
Eucalyptus spp. have simple and usually alternate adult leaves with juvenile leaves starting off opposite to alternate (disjunct). In this species, juvenile and coppicing leaves are distinctively sessile, narrow lanceolate to linear, to 100 mm long to 20 mm wide, paler on the lower surface and arranged in opposite pairs, with a very strong peppermint odour (useful in identification). Adult leaves are the same shade of green on both sides, lanceolate to falcate or almost linear, to 120 mm long and to 15 mm wide, tapering to a petiole to about 15 mm long, also with a pungent peppermint odour (very useful for identification).
The primary inflorescence of “eucalypts” (Angophora / Corymbia / Eucalyptus) is an umbellaster (an umbel-like cluster of flowers). In the flowers of Corymbia and Eucalyptus, the petals and sepals are fused into the distinctive calyptra / operculum (bud cap) which is shed when the flower opens (in some species, 2 bud caps (opercula) are shed). The flowers are conspicuously staminate – where many stamens are basically taking over the role of the petals, all surrounding one central carpel. In this species,The flower buds are arranged in clusters (umbellasters) in leaf axils on peduncles to 12 mm long. In this species, at least 11, and up to 20 or so buds, are produced in each umbellaster – a useful identification feature (as hardly any NSW eucalypt has that many buds. Note: probably the only eucalypt which exceeds this is Eucalyptus elata (River Peppermint) which can grow alongside this species in some habitats and can have up to 30 buds per umbellaster). Mature buds are club-shaped, to 5 mm long and to 3 mm wide with a rounded or conical operculum / calyptra that is shorter and narrower than the floral cup at the join. Flowers are white and very conspicuous and occur from October to January.
The fruit of eucalypts are a woody capsule (commonly called ‘gum nuts’) which come in a wide variety of shapes with the top part having a sunken, flat or raised disc and with the valves inserted, disc-level, exserted to strongly exserted. In this species, the capsules are woody, cup-shaped, hemispherical or shortened spherical, to 6 mm long and to 7 mm wide with the valves enclosed or near rim level (look for the capsules to be in groups of 11-20).
A nice-enough tree in a garden but can grow large. They are some grandiose specimens in places such as the Southern Highlands of NSW, which reach 40 metres in height (Exeter, Bundanoon, Penrose etc). On sandy soils, they are usually shorter with a weeping habit of narrow foliage.
The fibrous bark can be covered in green lichen in moist areas. A very hardy tree. Not suited to small residential gardens. Would be a nice specimen tree in a park, large landscape or paddock. Not overly fussy of soil type. Can be grown on flat or sloping areas.
The foliage has a very strong peppermint odour.
Eucalypts can suffer problems from, caterpillars, leaf eating beetles, psyllids and borers to name a few. In undisturbed conditions, the numbers of eucalypt-feeding insects and their predators and parasites are in balance, so that they rarely cause tree death and most trees quickly recover from attack. In a home situation nature can get out of balance.
Eucalyptus can be propagated by seeds which is most common method or grafting.
Cuttings are difficult to start, but can be used in some species.
For further information refer to: http://anpsa.org.au/APOL2007/sep07-s1.html
There are two subspecies currently recognised in NSW:
• Eucalyptus radiata subsp. radiata – Central and Southern Tablelands and into Victoria and Tasmania.
• Eucalyptus. radiata subsp. sejuncta – which grows on the Northern Tablelands and has broad lanceolate leaves
Some botanists also recognise subsp. robertsonii which grows on the Southern Tablelands of NSW and Victoria. In NSW, this is recognised as Eucalyptus robertsonii.
Eucalyptus radiata has six known chemotypes of essential oil.
Eucalyptus is one of three similar genera that are commonly referred to as “eucalypts”, the others being Corymbia and Angophora.
It is well-known that Eucalyptus is a large and diverse genus. Between 700 and 950 known species are reported, occurring as far north as The Philippines, as well as Indonesia, New Guinea, Timor and Australia. Only 16 species reportedly occur outside Australia. They occur in all Australian states. NSW currently has about 250 species. (See this website for some detailed information: https://apps.lucidcentral.org/euclid/text/intro/learn.htm).
Regenerates after fire from lignotuber and epicormic growth as well as seed.
Eucalyptus – from Greek, eu, “well” or “true” and calyptus, referring to the calyptra (καλύπτρo) or operculum, which is a bud cap or covering which covers the developing flowers. The calyptra is a fusion of petals and/or sepals and is shed when the flower opens, leaving a flower with many stamens (staminate) surrounding one female part (carpel).
radiata – Latin meaning “radiating”, – referring to the flower bud clusters which have many buds splaying out forming a somewhat-circular shape.
This species is not considered to be at risk of extinction in the wild.
Field Guide to Eucalypts – Vol 1 South Eastern Australia’ M.I.H.Brooker and D.A.Kleinig. Blooming Books.
EUCLID – Eucalypts of Australia – Centre for Australian National Biodiversity Research – Eucalyptus radiata profile page https://apps.lucidcentral.org/euclid/text/entities/eucalyptus_radiata_subsp._radiata.htm
NSW Flora Online (PlantNET) – Eucalyptus radiata profile page