Eucalyptus gregsoniana

Eucalyptus gregsoniana, Wolgan Snow Gum is a tall shrub or small tree reaching a height of six metres, often seen as a mallee. 

It is found only in NSW, in two generally disjunct areas; immediately north and east of Lithgow and extending through the Blue Mountains to Lithgow; then on the southern tablelands, near Mongarlowe and Braidwood and extending north, to between Tarago and Nerriga, and as far south as east of Cooma (Wadbilliga State Forest).

It typically grows in dry sclerophyll woodlands on moist sandy soils.

The bark is smooth, white or grey and shed in ribbons.

Eucalyptus spp. have simple and usually alternate adult leaves with juvenile leaves starting off opposite to alternate (disjunct). In this species, juvenile leaves are grey-green, lanceolate to falcate, to 13 cm long and 4.5 cm wide. Adult leaves are 10 cm long and 2.5 centimetres wide, lanceolate, leathery and grey-green on both surfaces. The minor veins of leaves are almost parallel with the prominent mid vein – a useful identifying feature.

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, flowers are carried in umbellasters of 7-11. Flowers are 1 cm across, white and appear in spring.

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 pear-shaped or globular, to about 9 mm long and wide, with 3 to 4 valves at or near rim level.