Acer macrophyllum, the bigleaf maple or Oregon maple, is a large deciduous tree in the genus Acer. 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 of central California, and a tiny population occurs in central Idaho. Description Bigleaf maple can grow up to tall, but more commonly reaches tall and . The species' current national champion for size is located in Lane County, Oregon. It is tall with a crown spread of , with an average diameter at breast height (dbh) of about . The previous national champion is located in Marion, Oregon, and is tall with a crown spread of , with an average dbh of about . The bark is gray brown, darkening and developing ridges with age. The bigleaf maple has the largest leaves of any maple, typically across with five deeply incised palmate lobes, with the largest running to . The stems are long and contain milky sap. In autumn, the leaves turn gold and yellow, contrasting against backdrops of evergreen conifers. In spring, the tree produces flowers in pendulous racemes long, greenish-yellow with inconspicuous petals. It is hermaphroditic, bearing both male and female flowers in each raceme. The flowers appear in early spring, before the leaves. The fruit is a paired winged samara, each seed in diameter with a wing. Bigleaf maple begins bearing seed at about ten years of age. In May 2018 the oldest two Oregon maples in Europe, 175 years old, were removed from Trinity College Dublin (TCD), Ireland. The first had an interior which was beginning to rot, and it fell after inclement windy weather. The second, also infected, was cut down as the same fate was expected. Both were in the adjoining grassy area which was originally the cemetery of All Hallows and is now the Front Square of TCD. Chemical constituents The fallen leaves, blossoms, and seeds are concentrated with potassium, calcium, and other nutrients. Distribution and habitat Bigleaf maple can be found west of British Columbia's Coast Ranges and the Cascade Range, from Vancouver Island to California. It usually grows from sea level to elevations of , and more exceptionally . It can form pure stands on moist soils in proximity to streams, but is generally found within riparian hardwood forests or dispersed, (under or