Origin: Eastern North America (native in Ontario)
Silver maple is a medium to large tree with a broad rounded crown.Read more about Tree, Bark, Twigs
Leaves are palmately lobed, with 5 to 7 deeply cut lobes, the central lobe constricting at the centre of the leaf.Read more about Leaves
Flowers are borne in dense clusters that surround the twig, male and female on separate branches.Read more about Flowers
Fruits are pairs of winged seeds (samaras or maple keys); though often only one seed per pair develops.Read more about Fruit
Silver maple is a medium- to large-sized tree, up to 20 - 35 m (65' - 115'), and up to 100 cm (39") in diameter, with a broad rounded crown.
Leaves are 8 - 20 cm (3" - 7 3/4") long, palmately lobed, with 5 to 7 deeply cut lobes with sharp irregular teeth, the central lobe narrowing at the centre of the leaf.
Flowers are borne in dense clusters that surround the twig, male and female on separate branches, or even separate trees.
Fruits are pairs of winged seeds (samaras also called keys), though often only one seed per pair develops.
Silver maple is found on wet sites in mixed and deciduous forest throughout central and eastern North America.Classification
Until recently the maples belonged to their own family, Aceraceae. Current plant classification schemes now place maples in the soapberry family, Sapindaceae, along with horsechestnut and Ohio buckeye, which also have palmate leaves.
Silver maple naturally crosses with red maple (Acer rubrum), producing the hybrid Freeman's maple (Acer x fremanii), which has many cultivated varieties for urban planting. For a comparison of the leaves of silver, red and Freeman's maple see Oregon State University Dept of Horticulture website.
Derivation of names
Silver maple's species name (saccharinum) means sugary, in reference to the sap, though silver maple sap is not as sweet as that of sugar maple (Acer saccharum). The genus name Acer means sharp, referring to the sharp tips of the leaf lobes of most maples. The common names, silver and white, refer to the colour of the underside of the leaves. The alternative name, soft, is the commercial name applied to silver maple wood.
Commercial use and wildlife value
Silver maple's wood is soft and brittle and is used to make products such as crates, pulp, and veneer. Silver maple is an important source of food for small mammals and birds. Its flowers, which appear late in winter, provide food for squirrels at a time when their winter food stores may be depleted. Hollow trunks and cavities in branches provide shelter and/or nesting sites for urban wildlife including birds such as wood ducks and mammals such as squirrels and raccoons.
Silver maple's place in Toronto's urban forest
Silver maple is a prized urban tree and is one of the 10 most common trees in Toronto. Silver maple has been planted in many Toronto parks and along city streets, particularly in residential areas. For example, Palmerston Blvd, seen here in the 1920s, and again in 2002, was planted exclusively with silver maples in the early 1900's. Today many of these trees are reaching the end of their lifespan.
Avenues of large silver maples can also be seen at Coronation Park where 150 trees were planted in a ceremony on Coronation Day, 12 May 1937. Read about the history of this event here.
Landscape value and potential for home planting
Silver maple is a very large tree that requires space because its roots spread aggressively, and when confined often buckle sidewalks and clog underground pipes. The wood of silver maple is soft and its branches brittle, so it is susceptible to damage during storms and high winds. Silver maple grows best in moist, slightly acidic soils. Silver maple leaves are very thin, degrading easily when composted or used directly as garden mulch.
Pests and diseases: Like other maples, silver maple is susceptible to various pests including the commonly seen maple gall mite, Vasates sp, that produces raised red projections and the tar spot fungus, Rhytisma acerinum, which produces black spots that are especially obvious in wet summers. Though both of these can be ugly they are not usually damaging to the tree. For up to date information on pests visit Natural Resources Canada fact sheet.
Find trees on Tree Tour maps at Canadian Tree Tours: