Sycamore maple

Appearance

The sycamore maple is a large deciduous tree that reaches 20–35 m tall at maturity, with a broad, domed crown. On young trees, the bark is smooth and grey but becomes rougher with age and breaks up in scales, exposing the pale-brown-to-pinkish inner bark. The leaves are opposite, large, 10–25 cm long and broad with a 5–15 cm petiole, with leathery texture, palmately veined with thick veins protruding on the underside surface, with five lobes with toothed edges, and dark green in colour with whitish underside; some cultivars have purple-tinged or yellowish leaves. The leaf-stalk is frequently tinged red. The leaves are often marked with black spots or patches which are caused by the fungus ''Rhytisma acerinum''.

The monoecious yellow-green flowers are produced in spring on 10–20 cm pendulous racemes, with 20–50 flowers on each stalk. The 5–10 mm diameter seeds are paired in samaras, each seed with a 20–40 mm long wing to catch the wind and rotate when they fall; this helps them to spread further from the parent tree. The seeds are mature in autumn about 6 months after pollination.

The sycamore is able to produce suckers from roots when they are exposed to sunlight after the mature tree has fallen.

Status

It is considered an environmental weed in some parts of Australia, and also Mount Macedon, near Daylesford, parts of the Dandenongs and Tasmania where it is naturalised in the eucalypt forests, New Zealand, the United States, environmentally sensitive locations in UK and Norway.