Eucalyptus deanei

Eucalyptus deanei, more commonly known as the Deane's Gum or Blue Mountain Gum, is one of those large trees that populate the vast mountainous forests of southeast Australia. The most beautiful specimens reach 65 to 80 metres (213 feet 4 inches to 262 feet 6 inches) in the Blue Mountains National Park. With an incredible stature, it stands out for its very straight trunk covered with particularly colourful bark that contrasts well with the lush green vegetation. Its cream-white flowering is quite discreet, amidst the mass of foliage, but extremely fragrant and attractive to bees. With a hardiness of around -7 to -8°C (19.4 to 17.6 °F), it will prefer a temperate, coastal climate, in dry to moist, well-drained soil, not too dry in summer. Fast-growing, this beautiful remarkable tree structures the landscape of a garden large enough to accommodate it.

Eucalyptus deanei, synonymous with E.saligna var. parviflora, is an endemic species from the east of Australia, more particularly from the centre of the east coast of New South Wales, in an area ranging from Picton to Singleton and an area extending from Armidale to the extreme southeast of Queensland. It thrives in high, humid forests on sandy alluvial soils, and on slopes and granite plateaus, at an altitude between 300 and 1000 m (984 ft 4 in and 3280 ft 10 in). In these regions, the climate is subtropical with strong continental influences, resulting in a cold winter atmosphere (3 to 15°C (37.4 to 59 °F)) and mild to warm in summer (15 to 27°C (59 to 80.6 °F)), with precipitation of 1100 mm spread throughout all months of the year. Belonging to the Myrtaceae family, it is commonly called: Deane's Gum or Blue Mountain Gum or sometimes Round Leaf Gum. Henry Deane (1847–1924), a railway engineer, but also a renowned botanist especially in the fields of eucalyptus, orchids and palaeobotany, gave his name to this species.

This eucalyptus forms a large tree, with a straight trunk and a spreading crown. Fast-growing, in its natural habitat it reaches a height of 40 to 50 m (131 ft 2 in to 164 ft) and 15 to 25 m (49 ft 2 in to 82 ft) in span. It generally rises on a single trunk that starts from a stump named lignotuber* located just below the surface of the soil. When young, it has rounded or square branches, bearing juvenile foliage, consisting of leaves, petiolate, opposite on 6 nodes, then alternate, round to ovate, 4 to 10 cm (1.6 to 3.9 in) long, 3 to 6 cm (1.2 to 2.4 in) wide, green and shiny. Then, as it develops, the petiolate leaves are alternate and take a lanceolate shape of 8 to 18 cm (3.1 to 7.1 in) long, 2 to 4 cm (0.8 to 1.6 in) wide, a pretty dark green on top, paler underneath. The leaves are very aromatic and give off a menthol fragrance when crushed, rich in eucalyptol. As it ages, the bark on the lower part of the trunk is evergreen, scaly, grey or brown; and on the upper part the bark is smooth, powdery, white or cream, with yellow, pink, grey or orange spots. The flowering mainly occurs in spring and early summer, but occasionally at other times. It does not constitute a real point of interest, drowned in the mass of foliage. The inflorescence, arranged in the axil of the leaves, on a short peduncle, is composed of 7, 9 or 11 floral buds gathered in a tight umbel which bloom into small flowers with numerous cream-white anthers, forming a pompon. Rich in nectar, they are very attractive to bees and birds. After flowering fruits, called "gumnuts", appear in the form of a woody, hemispherical capsule, divided into 3 or 4, which contain seeds 1 to 2 mm (0 to 0.1 in) long and brown or grey.

This eucalyptus has a *lignotuber, constituted by a swelling rich in starch that forms on the roots just below the surface of the soil. This organ allows it to restart from the stump in case of severe frost, fire or pruning to the ground. The plant also produces many shoots from dormant buds located under its bark, which allows it to respond well to pollarding, topping or more severe pruning.

Deane's Gum is an attractive and robust tree that finds a place in a large garden planted in isolation in an open space to appreciate the beauty of its bark and the elegance of its stature. In order to highlight its architectural habit, it is trained on a single trunk. With a hardiness of around -7 to -9°C (19.4 to 15.8 °F), it will prefer a temperate, coastal climate, with dry to moist, well-draining soil, but it hates periods of long droughts or soils that are too clayey or too limestone. Comfortable in moist soils, but not swampy, it has the ability to dry them out. With a highly developed root system, one must be vigilant about the choice of its location, keeping it away from the foundations of a house, or pipes.