| General Description | Eucalyptus umbra is a small to medium evergreen tree or small evergreen shrub with green, semi glossy leaves that are 10-14 cm long, and 2.5-3.5 cm wide. They remain green throughout the year and may drop during the dry season. It produces 7-11 white flowers that are arranged in an umbrella-like shape. |
| ID Characteristic | Eucalyptus umbra can be distinguished from other stringybark species by the densely reticulate venation of the adult leaves, the veins have web-like network. The fruit is also flat topped, and the juvenile leaves are wider than other species found nearby. |
| Shape | Grows upright and true in full sun, will follow the sun if it is in a shady area. |
| Landscape | Eucalyptus umbra makes a good shade tree on a medium to large sized property. This tree is also used for lumber, the heartwood especially is useful for fence posts, floors, and construction materials. |
| Propagation | Eucalyptus umbra can be propagated from shoots that sprout off the lignotuber after significant fire damage or insect damage happens to the tree. The shoots can often be used as cutting material. A more effective way is to use seeds; surface sow late winter early spring in a greenhouse. E. umbra is a high-altitude species, so it requires 6-8 weeks cold stratification at 2°C. As soon as the second set of juvenile leaves appear, the seedlings should be potted, any longer and they may not do well. Plant them outside in their permanent spots in early summer and give them protection during first winter to avoid cold damage. |
| Cultivation | This tree grows well when average daily temperatures are quite warm and dry. It prefers well-draining, poor, sandy soil. It requires full sun and annual precipitation of 600-1700 mm in a humid area. E. umbra cannot tolerate sudden temperature drops and can only tolerate temperatures as low as -2°C in a dormant state. |
| Pests | Susceptible to caterpillars, borers, leaf eating beetles, psyllids (jumping plant lice). In the natural environment the number of pests and their predators are balanced. However, this may differ in a cultivated setting. |
| Notable Specimens | Adelaide Botanic Gardens, Adelaide, South Australia. Accession number: W20011398*A. Ku-ring-gai Chase National Park, Sydney, New South Wales, Australia. |
| Habitat | Eucalyptus umbra grows in the high-altitude (1000m above sea level) coastal regions of New South Wales between Sydney and Grafton, as well as further north to southeast Queensland. It prefers poor, shallow, dry soils in sclerophyll forests or woodlands. Sclerophyll means a woody plant with evergreen leaves that are tough and thick to reduce water loss. |
| Bark/Stem Description | The bark is persistent throughout. Stringy or fibrous, thin, reddish-brown, or greyish brown to grey. |
| Flower/Leaf Bud Description | The individual flower buds are arranged on 3-7 mm long pedicels which grow from a 6-20 mm long peduncle from the ends of branchlets. Leaf buds are ovoid to fusiform, 3-4 mm in diameter, 7-9 mm long. |
| Leaf Description | Juvenile leaves are sessile and opposite, held horizontally, lanceolate to broadly ovate. Juvenile leaves are 3.5-10 cm wide and 8-10 cm long, lanceolate, amplexicaul, and a discoloured green colour. Adult leaves are alternate, falcate to lanceolate, base tapering to a 1-2 cm long petiole, concolorous, dull, or glossy, green, densely to very densely reticulate, intramarginal vein parallel to and remote from margin, side veins 45° to midrib, oil glands island, intersectional or secure. |
| Flower Description | Flowers are arranged on 3-7 mm long pedicels attached to a 6-20 mm peduncle protruding from the ends of the branchlets. 7-11 white flowers per umbel, flowering occurs from September to February. Pollinated by bees that harvest the nectar. |
| Fruit Description | Fruits are cup-shaped to hemispherical on 2-8 mm long pedicels, they are 3—7 mm long, 6—10 mm wide, level or slightly descending, raised-convex, disc broad, 3—5 valves near rim level or enclosed. |
| Colour Description | Leaf buds are yellow. Juvenile leaves start out yellow, turning red before finally maturing to a uniform green. The leaves remain green throughout the year. The bark is reddish-brown to greyish-brown. Flowers are white, and fruits are golden brown. Juvenile branches are red. The veins of mature leaves are yellow. |
| Texture Description | Leaves have a glossy or dull appearance; bark has a medium texture. |