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Eucalyptus racemosa

Snappy Gum or Narrow-leaved Scribbly Gum

Family: Myrtaceae

A tree, growing to 20 metres or more, forming a lignotuber.

It is found along the coast, tablelands and western slopes in NSW, from Bombala, extending north-west to Bathurst and west to Canberra (ACT), north to Gympie and Bundaberg in south-eastern Queensland.

It grows in dry sclerophyll woodland and forest, sometimes in pure stands, on poor sandstone and sandy soils as well as other rocky substrates, in mid to high rainfall areas.

Bark is smooth, mottled white, yellow, grey or cream-coloured, typically with scribbles caused by scribbly gum moth-larvae.

Eucalyptus spp. have simple and usually alternate adult leaves with juvenile leaves starting off opposite to alternate (disjunct). In this species, young plants and coppice regrowth consists of dull blue-green, ovate leaves to 170 mm long to 85 mm wide and petiolate. Adult leaves are the same shade of blue-green on both sides, lanceolate to falcate or elliptic, to 200 mm long and to 15 mm wide on a petiole to 25 mm long.

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 leaf axils in umbellasters of eleven to fifteen; the individual buds on pedicels to 6 mm long. Mature buds are oval to 5 mm long and to 3 mm wide with a rounded or conical operculum or calyptra. Flowers are white and mainly occur from July to September.

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, capsules are woody, pyriform to ovoid, to 5 mm long and to 7 mm wide with the valves near rim level. The top of the capsule is usually maroon-red in colour.

In the garden

A nice tree in an open native garden and it can also be grown as a mallee.

Can be a nice specimen tree in a lawn area with its trunks displaying shades of white, grey and yellow/dark-cream at times. It is fast growing and needs well drained soils. Needs an open position in full sun. A useful tree for ridgetop gardens and landscapes on higher ground with shallow soils.

Authors note: This author purchased a seedling labelled E. haemastoma which only grows to 10 m and is ideal for the home garden. Unfortunately, the tree turned out to be E. racemosa which has smaller leaves and capsules. This plant now dominates my smallish backyard now 40 years after planting.

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.

Propagation

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

Other information

There have historically been 5 scribbly gum taxa recognised in NSW (E. haemastoma, E. racemosa, E. rossii, E. sclerophylla and E. signata). Recent studies have lumped these taxa into 3 entities as follows:
Eucalyptus haemastoma 
– Eucalyptus racemosa subsp. racemosa
– Eucalyptus racemosa subsp. rossii

However, this revision was not accepted by all herbaria. Genetic research still continues as the taxa are known to intergrade with likely hybridisation. Taxa may be lumped in the future. 

Eucalyptus racemosa is distinguished from E. haemastoma by having smaller fruit and often narrower leaves.

Regenerates very readily after fire from the lignotuber and epicormic shoots.

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).

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).

racemosa – Latin meaning “having racemes”, which is a misnomer, as it does not have flowers in racemes. However, it has the appearance of such when in full flower

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.

NSW Flora Online (PlantNET) – Eucalyptus racemosa profile page 
https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Eucalyptus~racemosa

EUCLID – Eucalypts of Australia – Centre for Australian National Biodiversity Research – Eucalyptus racemosa subsp. racemosa profile page https://apps.lucidcentral.org/euclid/text/entities/eucalyptus_racemosa_subsp._racemosa.htm

By Jeff Howes. Editing and additional text by Dan Clarke.