Eucalyptus dura

Eucalyptus dura is a species of small to medium sized tree that is endemic to south-eastern Queensland. It has rough, dark grey to black "ironbark", lance-shaped adult leaves, flower buds in groups of seven, white flowers and conical fruit.

Description
Eucalyptus dura is a tree that typically grows to a height of 25 m and forms a lignotuber. It has dark grey to black ironbark on the trunk and larger branches, smooth grey to cream-coloured bark on branches less than 30 mm in diameter. Young plants and coppice regrowth have lance-shaped to egg-shaped leaves 95-140 mm long and 20-40 mm wide. Adult leaves are lance-shaped, sometimes curved, 90-180 mm long and 15-33 mm wide on a petiole 10-35 mm long. The leaves are the same or a similar glossy green on both sides. The flower buds are arranged in groups of seven on the end of branchlets on a branched peduncle 7-25 mm long, the individual buds on a pedicel 4-8 mm long. Mature buds are oval to pear-shaped, 7-9 mm long and 4-5 mm wide with a conical operculum that is narrower and shorter than the floral cup. Flowering mainly occurs from April to June and the flowers are white. The fruit is a woody, conical capsule 6-10 mm long and 5-7 mm wide on a pedicel 2-10 mm long with the valves below the level of the rim.

Taxonomy and naming
Eucalyptus dura was first formally described in 1991 by Lawrie Johnson and Ken Hill from a specimen collected from Turkey Mountain in the Barakula State Forest in 1984. The specific epithet (dura) is a Latin word meaning "hard" or "tough", referring to the bark of this tree.

Distribution and habitat
This ironbark grows in grassy and dry forests in sandy soil, usually on higher places. It occurs between the Biggenden, Chinchilla and Boonah districts in south-east Queensland.

Essential oils
The leaves of E. dura are rich in oils, particularly β-phellandrene and 1,8-cineole. These oils may be suitable for development of a bacteriostat.