Acer macrophyllum, the bigleaf maple or Oregon maple, is a large deciduous tree in the genus Acer. It is native to western North America. In addition to uses by animals, it is of some culinary and woodworking interest.

thumb|Large Acer macrophyllum leaf in Washington State

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 stems are long and contain milky sap.

The fruit is a paired winged samara, each seed in diameter with a wing.

Chemistry

The fallen leaves, blossoms, and seeds are concentrated with potassium, calcium, and other nutrients.

It usually grows from sea level to elevations of , and more exceptionally . Though very rare north of Vancouver Island, it is cultivated in Prince Rupert, near Ketchikan, and in Juneau.

Ecology

The tree can live in a wide range of habitats, but thrives in fairly well-hydrated hardwood forests, occurring with red alder, black cottonwood, and willows. It is fairly shade tolerant, but not as much so as vine maple, and benefits from disturbances. It spreads and grows vegetatively from cuttings and stumps of any size in a prolific manner. 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.

A western Oregon study found that 60% of bigleaf maple seedlings over tall had been browsed by deer, most several times.

Bigleaf maple is preferred as habitat by the barred owl, an invasive species to coast range habitat, and the presence of the tree is positively associated with Hammond's flycatchers.

  • 'Santiam Snows' — green leaves speckled with white
  • 'Seattle Sentinel' — upright, columnar plant habit

Uses

Native Americans grew sprouts from the seeds for consumption, wove baskets from the inner bark, and used the leaves to cover food in cooking pits. They also carved the wood into dishes, utensils, and canoe paddles.

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.

The buds of the tree are also considered edible. They are often fried and made into fritters.

Lumber

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

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thumb|This maple leaf was found on our property by near a very large old bigleaf maple tree.

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File:Acer macrophyllum 1.jpg|Acer macrophyllum in early spring

File:Acer macrophyllum 2.jpg|The -long raceme of greenish-yellow flowers appear as the leaves are developing in the spring.

File:MossesHohRainForest 7306.jpg|Moss and Licorice fern on Bigleaf maple in Hoh Rainforest in Olympic National Park, Washington

File:Tall bigleaf maple.JPG|Bigleaf maple in the McKenzie River valley in western Oregon

File:"WORLD'S LARGEST BIGLEAF MAPLE" IN ENGLISH CAMP - NARA - 545275.jpg|"WORLD'S LARGEST BIGLEAF MAPLE" IN ENGLISH CAMP on San Juan Island, Washington

Acer macrophyllum 6.jpg|Fallen Acer macrophyllum leaf in fall near Cashmere, Washington

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References

  • photo of herbarium specimen at Missouri Botanical Garden, collected in Yolo County, California, in 1903
  • Jepson Manual