Silver maple is often planted by gardeners who desire a rapidly growing, beautiful shade tree. As the common name implies, this tall, deciduous native of the eastern US takes on a silvery appearance when its two-toned leaves dance in the wind, and it typically grows to a height of 60 to 80 feet in full or part sun. Young trees tend to have irregular, upright branching that becomes dense and spreading with maturity. Also known as swamp or river maple, it often grows in wetland areas in the wild and as a wet-site tree in rural settings; however, it adapts to a wide range of soils, including wet or dry, clay, sandy, rocky, and rich loam. It tolerates salt, drought, and air pollution, making it a popular urban tree throughout Ohio. Reddish buds appear from early to mid-spring before the leaves develop, providing an important food source for squirrels when little else is available. Winged fruits, or samaras, develop several weeks after the spiky red flowers have bloomed. The seeds are extremely popular with birds and mammals, and they’re also enjoyed by human foragers (see Medicinal and Edible section below).
 
Silver maple has several distinguishing characteristics. Its leaves are the most deeply indented of any maple species. The lower branches become pendulous and turn up at the tips. The canopy can be 60 feet wide, and the roots extend several feet beyond the canopy’s width. They often protrude above the soil, making it hard to grow grass or run the lawnmower underneath. One suggestion to try is to plant drought-tolerant perennials with shallow roots, such as wild ginger, in the shaded area under the canopy. Because of its extensive, shallow root system and its tendency to lose branches during storms, silver maple needs to be planted strategically. It’s illegal in some cities to plant silver maples near particular features because of the damage they have caused to sidewalks, drain tiles, foundations, and septic systems. (Pipes commonly fail due to age or movement of the soil, but once there’s a break in the pipe, roots may enter and grow.) But this doesn’t mean silver maples have no place in the landscape. They flourish in poor soils where other species cannot survive, and they’re perfect for larger areas that are a good distance from houses, sidewalks, and sewer systems.
 
To encourage good growth, water young maples regularly for several years. Fertilize in early spring, and be careful not to spread a thick layer of mulch over the shallow roots. Prune annually, and, if needed, use cabling to stabilize multiple trunks.
 
Native habitats include moist floodplain woodlands, riverbanks, and swamps. Silver maple is an ideal shade tree for ponds, stream banks and large lawns.
 
Plant Characteristics:
Grows 60-100’ tall and up to 60’ wide.
 
Grows in full or part sun.
 
Prefers rich, wet to moist, slightly acidic soils but tolerates many other soil types and occasional standing water. Drought tolerant once established.
 
Flowers appear February-March and are primarily wind pollinated. Clusters of 3-6 flowers grow in densely crowded umbels along the twigs. Males contain greenish-yellow stamens, while females have a hairy pistil with two red styles. Samaras up to 2” long mature and disperse October-December.
 
Opposite leaves up to 6" long and 4" across grow in pairs along twigs and smaller branches. Leaves have 5 deep lobes divided into shallow secondary lobes; all of the lobes are sharply cleft with pointed tips and toothed margins.
 
Short, broad trunk is 2-4’ in diameter at maturity, but it often divides near the ground into smaller trunks. The bark of young trees is light gray and fairly smooth, while twigs are reddish brown, smooth, and scattered with white lenticels. Mature bark is gray and rough-textured, with flattened scales and straight or curving furrows. On very old trees, the scales loosen and become shaggy.
 
Wildlife Value:
Host plant for 273 species of Lepidoptera larvae, including the eastern tiger swallowtail, luna moth, and mourning cloak butterfly. Other species of insects also feed specifically on silver maple. Bees gather pollen from the male flowers. The seeds are eaten by birds such as grouses, grosbeaks, bobwhites, sapsuckers, goldfinches, and wild turkeys and by many mammals, including raccoons, red and fox squirrels, chipmunks, rabbits, voles, and mice. The tree is an important source of food and construction material for beavers, and the foliage and twigs are browsed heavily by deer. Cavities in mature trees provide nesting habitat or dens for screech owls, wood ducks, squirrels, raccoons, and opossums.
 
Medicinal, Edible, and Other Uses:
Silver maple sap and bark has been used to treat coughs, stomach cramping, dysentery, sores, gonorrhea, and measles. Native Americans also used fermented sap along with thimbleberries to make alcohol.
 
While it’s common knowledge that maple sap can be concentrated into syrup, it’s not as well known that the seeds of the samaras are a healthy treat for humans. Red and silver maples offer early crops of the protein- and carbohydrate-rich seeds, and a second crop is available from sugar maples, striped maples, and boxelders in early autumn.
 
Samaras eaten straight from the tree are usually tastier. To release the seeds, peel off the outer casing. They may be eaten plain, added to salads, roasted, boiled/steamed and buttered, or dried and ground into flour.
 
Author/forager Linda Runyon recommends making maple patties. She collects two cups of samaras and chooses the mid-sized fruits for shelling: “They’re the tastiest. The big ones are starting to dry out, and the little ones are not quite ready.” After mashing the shelled seeds into a thick pulp, she shapes them into small patties, fries them in oil, and serves them with maple syrup.
 
The Chippewa boiled the bark of silver maple with the bark of other trees to make a substance that they used to remove rust. The Cherokee carved the soft wood into decorations, and the Ojibwa used the wood in arrows and the roots as bowls in a game called “pugasaing,” a dice-like game played by children and adults.
 
The leaves are packed around apples to help preserve them, and the stems are used in making baskets.
 
Silver maple wood is somewhat soft and is used to make furniture, veneer, fuel, flooring, crates/pallets, paper, interior trim, woodenware, musical instruments, turned objects, wagons, and tool handles.
 
Caution: silver maple leaves, especially when wilted, are toxic to horses but not to pets or humans.