Eucalyptus globulus subsp.
bicostata is a tree that typically grows to a height of and forms a
lignotuber. The bark is mostly smooth, shedding in long strips to leave a white or greyish surface. There is sometimes rough, partially shed bark at the base of the trunk and ribbons of shedding bark in the upper branches. Young plants and
coppice regrowth have stems that are more or less square in cross-section, with a prominent wing on each corner. The juvenile leaves are
sessile, arranged in opposite pairs, elliptic to egg-shaped, the lower surface covered by a white, waxy bloom, long and wide. Adult leaves are arranged alternately, glossy green, lance-shaped to curved, long and wide on a
petiole long. The flower buds are arranged in groups of three in leaf
axils on a thick
peduncle long, the individual buds more or less sessile. Mature buds are glaucous, conical and warty, long and wide with two ribs along the sides and a flattened
operculum that has a central knob. Flowering mainly occurs between January and March and the flowers are white. The fruit is a woody, sessile, hemispherical to conical
capsule long and wide with two longitudinal ridges and the valves at about rim level. ==Taxonomy and naming==