River she-oak (Casuarina cunninghamiana)

Description

Casuarina cunninghamiana is a she-oak species of the genus Casuarina. The native range in Australia extends from Daly River in the Northern Territory, north and east in Queensland and eastern New South Wales. The River Oak is an attractive evergreen tree with fine greyish green needle-like foliage that grows to a height of 10–35 m (33–115 ft) with a spread of about 10 metres (33 ft). The trunk is usually erect, with dense rough bark. Flowers are reddish-brown in the male and red in the female. Cones are small, nearly round to elongated and about 10 millimetres (0.39 in) across. Trees are usually found in sunny locations along stream banks and swampy areas. It's widely recognised as an important tree for stabilising riverbanks and for soil erosion prevention accepting wet and dry soils. The foliage is quite palatable to stock. C. cunninghamiana is frost tolerant down to around −8 °C (18 °F) and is widely used effectively as a screening plant. It is useful on windy sites and is also suited to coastal areas. C. cunninghamiana has been introduced into several other countries for the purpose of agroforestry. The general shape of the tree is conical with tiered, horizontal branches that are often somewhat pendulous toward the tips. Cunninghamia bears softly spined, leathery, stiff, green to blue-green needle-like leaves that spiral around the stem with an upward arch; they are 2-7 cm long and 3-5 mm broad at the base, and bear two white or greenish-white stomatal bands underneath and sometimes also above. The foliage may turn bronze-tinted in very cold winter weather. The cones are small and inconspicuous at pollination in late winter, the pollen cones in clusters of 10-30 together, the female cones singly or 2-3 together. The seed cones mature in 7-8 months to 2.5-4.5 cm long, ovoid to globose, with spirally arranged scales; each scale bears 3-5 seeds. They are often proliferous (with a vegetative shoot growing on beyond the tip of the cone) on cultivated trees; this is rare in wild trees, and may be a cultivar selected for easy vegetative propagation for use in forestry plantations. As the tree grows its trunk tends to sucker around the base, particularly following damage to the stem or roots, and it then may grow in a multi-trunked form. Brown bark of mature trees peels off in strips to reveal reddish-brown inner bark. Older specimens often look ragged, as the old needles may cling to stems for up to 5 years. This tree can be mistaken for the rare Torreya taxifolia, one visible difference being the Cunninghamia's bronze autumn branches which are shed and pile beneath it, as well as the propensity for this tree to have more than one trunk. The Torreya is known as "Florida's gopher wood," as well as "stinking cedar" and the crushed leaves some say smell like tomato, whereas the Cunninghamia leaves do not smell.