Eucalyptus leucoxylon commonly known as Blue Gum, White Ironbark or Yellow Gum belongs to Family Myrtaceae. This species is a small to medium-sized tree, endemic to Australia. It is widely distributed on plains and nearby mountain ranges of NSW, Victoria or coastal South Australia. In NSW this species is known as the Blue Gum and in Victoria it is known as the Yellow Gum. This species I studied was Eucalyptus leucoxylon subsp. megalocarpa.
The upper part sheds irregularly in short ribbons or flakes, leaving a smooth, white, yellow or bluish colour.
Adult leaves are lanceolate (ie with the widest point at one-third or one-quarter of the leaf from the base, and tapering toward the apex), 8–15 cm long, 1–1.8 cm wide, green or grey-green. The leaves have numerous green and yellow island oil glands of varying sizes.
Red, pink or white flowers appear from mid autumn (March in Sydney).
The conspicuous part of the red flowers is mainly the red filament of the stamens. Instead of having petals and sepals, a flower has an hypanthium (base) in green colour and an operculum (lid) also in green. (The hypanthium and the operculum have similar originds as both petals and sepals combined.)
Fruit is globose or hemispherical, commonly 6 locular, 8–10 mm long, 8–10 mm diameter.
Eucalyptus leucoxylon is regularly planted for windbreaks, shade, honey production and for ornamental purposes.
The leaves are distilled for the production of cineole based eucalyptus oil which is used as a flavouring at low levels (0.002%) in various products, including baked goods, confectionery, meat products and beverages. It is toxic if ingested at higher than normal doses.
Acknowledgements
I would like to thank Mr Andrew Orme of the National Herbarium of New South Wales for his help in identifying the tree.
Bibliography
https://en.wikipedia.org/wiki/Eucalyptus_leucoxylon
http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Eucalyptus~leucoxylon
http://anpsa.org.au/e-leu.html