Acer macrophyllum, the bigleaf maple or Oregon maple, is a large deciduous tree in the genus Acer.
It can grow up to 157.80 feet (48.10 m) tall, but more commonly reaches 15–20m (50–65ft) tall. It is native to western North America, mostly near the Pacific coast, from southernmost Alaska to southern California. Some stands are also found inland in the foothills of the Sierra Nevada mountains of central California, and a tiny population occurs in central Idaho.
It has the largest leaves of any maple, typically 15–30cm (5.9–11.8in) across, with five deeply incised palmate lobes, with the largest running to 61 centimetres (24in). In the fall, the leaves turn to gold and yellow, often to spectacular effect against the backdrop of evergreen conifers.
The flowers are produced in spring in pendulous racemes 10–15cm (4–6in) long, greenish-yellow with inconspicuous petals. The fruit is a paired winged samara, each seed 1–1.5 centimetres (3⁄8–5⁄8in) in diameter with a 4–5-centimetre (1 5⁄8–2-inch) wing.
Bigleaf maple can form pure stands on moist soils in proximity to streams, but are generally found within raparian hardwood forests or dispersed, (under or within), relatively open canopies of conifers, mixed evergreens or oaks. In cool and moist temperate mixed woods they are one of the dominant species.
Bigleaf maple has been used for creating syrup but it is not common. This is because the sugar maple has a higher sugar content. Nevertheless, syrup production has become a localized industry in bigleaf maple groves where weather conditions (including sub-freezing winters) are especially suitable, such as near sea-level in British Columbia and at higher elevations along the West Coast from Washington through Northern California.
Maple syrup has been made from the sap of bigleaf maple trees. While the sugar concentration is about the same as in Acer saccharum (sugar maple), the flavor is somewhat different. Interest in commercially producing syrup from bigleaf maple sap has been limited. Although not traditionally used for syrup production, it takes about 40 volumes of sap to produce 1 volume of maple syrup.
Bigleaf maple is the only commercially important maple of the Pacific Coast region.
The wood is used for applications as diverse as furniture, piano frames and salad bowls. Highly figured wood is not uncommon and is used for veneer, stringed instruments, guitar bodies, and gun stocks.
The wood is primarily used in veneer production for furniture, but is also used in musical instrument production, interior paneling, and other hardwood products; the heartwood is light, reddish-brown, fine-grained, moderately heavy, and moderately hard and strong. In California, land managers do not highly value bigleaf maple, and it is often intentionally knocked over and left un-harvested during harvest of Douglas fir and redwood stands.
The Oregon Maples, which grew in front square, Trinity College Dublin, until this year were 4.96 and 4.11 meters in girth and both reached about 16 meters high.