Acer macrophyllum
Acer macrophyllum 1199.jpg
Bigleaf maple foliage
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Sapindales
Family: Sapindaceae
Genus: Acer
Section: Acer sect. Macrophylla
A. macrophyllum
Binomial name
Acer macrophyllum
Pursh 1813
Acer macrophyllum range map 1.png
Natural range
  • Acer auritum Greene
  • Acer dactylophyllum Greene
  • Acer flabellatum Greene 1912 not Rehder 1905
  • Acer hemionitis Greene
  • Acer leptodactylon Greene
  • Acer murrayanum Dippel
  • Acer palmatum Raf. 1836 not Thumb. 1784
  • Acer platypterum Greene
  • Acer politum Greene
  • Acer stellatum Greene

Acer macrophyllum, the bigleaf maple[2] or Oregon maple,[3] is a large deciduous tree in the genus Acer.

Big Leaf Maple can grow up to 48.10 metres (157.80 ft) tall,[4][5] but more commonly reaches 15–20 m (50–65 ft) 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.[2][6][7]

Large Acer macrophyllum leaf in Washington State


The bigleaf maple has the largest leaves of any maple, typically 15–30 cm (5.9–11.8 in) across, with five deeply incised palmate lobes, with the largest running to 61 centimetres (24 in).[8][9] In the fall, the leaves turn to gold and yellow, often to spectacular effect against the backdrop of evergreen conifers.

In spring, bigleaf maple produces flowers in pendulous racemes 10–15 cm (4–6 in) 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.[10]

The fruit is a paired winged samara, each seed 1–1.5 centimetres (3858 in) in diameter with a 4–5-centimetre (1+58–2-inch) wing.[6][9][8] Bigleaf maple begins bearing seed at about ten years of age.[10]


Bigleaf maples can form pure stands on moist soils in proximity to streams, but are generally found within riparian hardwood forests or dispersed, (under or within), relatively open canopies of conifers, mixed evergreens, or oaks (Quercus spp.)[11][7] In cool and moist temperate mixed woods they are one of the dominant species.[12] It is very rare north of Vancouver Island though cultivated in Prince Rupert,[13] near Ketchikan and in Juneau.[14]


The winged fruits are eaten by squirrels, and by grosbeaks in the winter.[15]Deer mice have been observed consuming bigleaf maple seeds in the spring in the Sierra Nevada. The foliage is browsed by ungulates such as black-tailed deer, mule deer, elk, and horses, as well as by mountain beavers and other rodents. [16][17]

A western Oregon study found that 60 percent of bigleaf maple seedlings over 25 cm (10 in) tall had been browsed by deer, most several times.[18]

Bigleaf maple is preferred as habitat by the barred owl, and the presence of the tree is positively associated with Hammond's flycatchers.[16]

In the more humid parts of its range, such as in the Olympic National Park, Big Leaf Maple's bark is covered with epiphytes such as club moss and licorice fern.[10]

Fire ecology

Bigleaf maple is not considered to be fire-resistant due to its thin bark, although large trees with thick bark may survive moderate-severity fires. However, along with red alder, bigleaf maple often dominates early postfire succession in Douglas-fir forests, and fire can increase its presence in a forest. [19] It spreads and grows vegetatively from cuttings and stumps of any size in a prolific manner. [10]



The bigleaf maple is the only commercially important maple of the Pacific Coast region.[11]

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.[20] Native Americans used the wood to make canoe paddles.[21]

In California, land managers do not highly value bigleaf maples, and they are often intentionally knocked over and left un-harvested during harvests for Douglas fir and redwood stands.[22]


Maple syrup has been made from the sap of bigleaf maple trees.[23] 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.[24] Although not traditionally used for syrup production, it takes about 40 volumes of sap to produce 1 volume of maple syrup.

Biggest tree

The current national champion bigleaf maple is located in Lane County, Oregon. It has a circumference of 11.8 m (38.6 ft)—or an average diameter at breast height of about 3.7 m (12.3 ft)—and is 36 m (119 ft) tall with a crown spread of 28 m (91 ft).[25] The previous national champion is located in Marion, Oregon, and has a circumference of 7.7 m (25.4 ft)—or an average diameter at breast height of about 2.5 m (8.1 ft)—and is 27 m (88 ft) tall with a crown spread of 32 m (104 ft).

Oldest trees

In May 2018 the oldest two Oregon Maples in Europe, 175 years old, were removed from Trinity College Dublin, 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.[26]


  • 'Mocha Rose' — foliage in various shades of pink over growing season; red flowers[27]
  • 'Santiam Snows' — green leaves speckled with white[28]
  • 'Seattle Sentinel' — upright, columnar plant habit[29]



  1. ^ Barstow, M.; Crowley, D.; Rivers, M.C. (2017). "Acer macrophyllum". IUCN Red List of Threatened Species. 2017: e.T193830A2284337. doi:10.2305/IUCN.UK.2017-3.RLTS.T193830A2284337.en. Retrieved 13 November 2021.
  2. ^ a b "Acer macrophyllum". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 6 January 2016.
  3. ^ BSBI List 2007 (xls). Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-06-26. Retrieved 2014-10-17.
  4. ^ Vaden, M. D. "World's Tallest Maple Discovery of 2012".
  5. ^ Poor, Kasi (2012-11-06). "The tall tale of 'Humboldt Honey' -- tree hunter says world's tallest maple is in Humboldt Redwoods State Park". Times-Standard. Archived from the original on 2013-12-03. Retrieved 2012-11-10.
  6. ^ a b Klinkenberg, Brian (Editor) (2014). "Acer macrophyllum". E-Flora BC: Electronic Atlas of the Plants of British Columbia []. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. Retrieved 2015-02-07.CS1 maint: extra text: authors list (link)
  7. ^ a b Sullivan, Steven. K. (2015). "Acer macrophyllum". Wildflower Search. Retrieved 2015-02-07.
  8. ^ a b Giblin, David (Editor) (2015). "Acer macrophyllum". WTU Herbarium Image Collection. Burke Museum, University of Washington. Retrieved 2015-02-07.CS1 maint: extra text: authors list (link)
  9. ^ a b Whittemore, Alan T. (2012). "Acer macrophyllum". In Jepson Flora Project (ed.). Jepson eFlora. The Jepson Herbarium, University of California, Berkeley. Retrieved 2015-02-07.
  10. ^ a b c d "Bigleaf Maple (Acer macrophyllum) | Oregon Wood Innovation Center". Retrieved 2021-05-11.
  11. ^ a b Fryer, Janet L. (2011). "Acer macrophyllum". Fire Effects Information System (FEIS). US Department of Agriculture (USDA), Forest Service (USFS), Rocky Mountain Research Station, Fire Sciences Laboratory – via
  12. ^ Wilson, Bert (2014). "Mixed Evergreen Forest". Nature of California. Las Pilitas Nursery.
  13. ^ "Trees of Prince Rupert" (blog). 2010.
  14. ^ "Trees Near Their Limits -- Alaska" (blog). 2010.
  15. ^ Peattie, Donald Culross (1953). A Natural History of Western Trees. New York: Bonanza Books. pp. 606–07.
  16. ^ a b "Acer macrophyllum". Retrieved 2021-05-05.
  17. ^ Fowells, H. A., ed. (1965). Silvics of forest trees of the United States. Agric. Handb. 271. Washington, DC: U.S. Department of Agriculture, Forest Service.
  18. ^ Fried, Jeremy S.; Tappeiner, John C.; Hibbs, David E. (1988). "Bigleaf maple seedling establishment and early growth in Douglas-fir forests". Canadian Journal of Forest Research. 18 (10): 1226–1233. doi:10.1139/x88-189.
  19. ^ "Acer macrophyllum". Retrieved 2021-05-05.
  20. ^ Arno, Stephen F.; Hammerly, Ramona P. (1977). Northwest trees. Seattle, WA: The Mountaineers. ISBN 9780916890506.
  21. ^ Whitney, Stephen (1985). Western Forests (The Audubon Society Nature Guides). New York: Knopf. p. 395. ISBN 0-394-73127-1.
  22. ^ Bolsinger, Charles L. (1988). "The hardwoods of California's timberlands, woodlands, and savannas". Resource Bulletin PNW-RB-148. Portland, OR: United States Department of Agriculture, Forest Service, Pacific Northwest Research Station.
  23. ^ Ruth, Robert H.; Underwood; J. Clyde; Smith, Clark E.; Yang, Hoya Y. (1972). "Maple sirup production from bigleaf maple" (PDF). PNW-181. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station.
  24. ^ "Maple syrup" (PDF). Island Net. Archived from the original (PDF) on September 25, 2006.
  25. ^ "Bigleaf Maple (Acer macrophyllum)". National Register of Big Trees. American Forests. 15 September 2016.
  26. ^ "Stress the likely cause of tree death in Trinity College, says expert".
  27. ^ "Mocha Rose Big Leaf Maple (Acer macrophyllum 'Mocha Rose') at GardenWorks".
  28. ^ "Japanese Maples - Acer macrophyllum 'Santiam Snows'".
  29. ^ "Acer macrophyllum 'Seattle Sentinel' | Landscape Plants | Oregon State University". Retrieved 2021-05-11.

External links