Brief Summary

Read full entry
The genus Acer (maples) includes approximately 125 species of trees and shrubs distributed through Asia, North America, Europe, and Northern Africa (van Geldren et al. 2010). The genus is characterized by opposite, palmately lobed leaves, and a distinctive fruit, a samara, formed of pair of nutlets with stiff, fibrous papery wings that aid in wind dispersal. Children have long referred to samaras as helicopters or whirlybirds; researchers have recently shown that the wings do provide a helicopter-like lift to seeds dispersed in a wind tunnel, as shown in this video by David Lentink available from Caltech (Svitil 2009; Lentink et al. 2009).

Maples have diverse cultural uses and economic importance. They are widely planted as ornamentals and street trees, with thousands of horticultural varieties and cultivars propagated by cuttings, tissue culture, budding or grafting. A. palmatum (Japanese maple) alone has 350 cultivars that are grown in Europe and North America (Vertrees and Gregroy 2009). Acer platanoides (Norway maple) is popular in urban areas because it is fast-growing and cold-resistant, but it is invasive in Eastern North America.

Maples are so diverse and popular that numerous arboretums around the world feature them in special collections known as aceretums. Maples are a popular choice for the art of bonsai. Viewing the dramatic autumn foliage of maples has spawned traditions and supported tourist industries in countries ranging from Japan and Korea (where the custom is called “momijigari” and “Danpung-Nori,” respectively, Wikipedia 2011) to “leaf-peeping” in southeastern Canada, the Northeastern and Northwestern United States, and British Columbia.

Maples were an important source of sugar and winter nutrition for natives of North America before European settlement (Henshaw 1890), and production of maple syrup continues to be a multimillion dollar industry in the U.S. and Canada (NASS 2011). Many maples, including A. macrophyllum,A. rubrum and A. saccharinum, contain sugars and can be used for syrup, but the sap of A. saccharum (sugar maple) is most often used because it has the highest sucrose content (2–8%). It takes approximately 40 liters of sap to make 1 liter of syrup. The sap of A. pseudoplatanus has been made into a sweet fermented beverage in some parts of Europe [Hedrick 1919]). Maple seeds and even leaves can be eaten, along with the inner bark (Plants for a Future 2011).

Maple wood is valuable commercially for uses including fine cabinetry, flooring, musical instruments, and many more. (See Uses in full entry.)

Maples are dominant or abundant in several North American forest types. In 2002, two maple species (A. rubrum and A. saccharum) were among the top 10 most common tree species in the U.S. (FIA 2011). Maple seeds, buds, leaves, and flowers serve as food for dozens of species of birds and small mammals (Martin et al. 1951), as well as numerous lepidopteran larvae and aphids. Because maples flower in early spring, their pollen is an important food for Apis mellifera (honeybees) and other insects. Maples are affected by damaging fungal diseases caused by organisms including Verticillium, Cryptostroma species, Phytophthora, and Ganoderma, as well as widespread but less severe infections known as “tar spot” (Rhytisma species), and mildew (Uncinula species).


Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Jacqueline Courteau

Supplier: Jacqueline Courteau

Belongs to 1 community


EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!