Trees & Shrubs of the Eloise Butler Wildflower Garden

The Black Sugar Maple is considered by some authorities to be a subspecies of the Sugar Maple, Acer saccharum and the plant will be found listed as Acer saccharum Marshall subsp. nigrum (F.Michx.) and sometimes as Acer nigrum x saccharum or simple as Acer saccharum nigrum. Minnesota authorities treat the tree as a separate species.

Black Sugar Maple is a native deciduous tree with a dense rounded crown, growing 60 to 80 feet high with a trunk diameter of 2 to 3 feet. The bark is dark gray to blackish becoming thick with age into deeply furrowed plates. The national champion Black Maple (as of 2021) is located in York County ME measuring 85 feet high, 98 foot crown spread, 170 inches in circumference and scoring 280 points.

The twigs are brown and slender when young with numerous light colored lenticels. The younger shoots will be green with some fine hair. Buds are reddish-brown with some green and with fine hair. Terminal buds are multiple, usually 3 with the center bud much larger, and the lateral buds on the twig are fairly tight to the twig.

The leaves are opposite, 4 to 5-1/2 inches long and wide, with 3 (sometimes 5) broad long-pointed lobes. The lobe sinuses are rounded but the sinuses of the lower lobes are more closed than those of Sugar Maple. The edges are wavy and usually drooping and sometimes there are a few blunt teeth. Main leaf veins all rise from the base. The upper surface is a dull green, but darker than the Sugar Maple, the lower surface paler with some soft hairs on and near the veins. The leaf stalks may have some fine hair. Fall color is a deep yellow to yellowish orange.

Flowers: The tree can be monoecious, that is with separate male and female flowers or dioecious, with the flowers on different trees. Male flowers (staminate) are in drooping umbels (tassel-like clusters) up to 3 to 4 inches long, on hairy stalks. Each cluster will have 8 to 14 flowers and each individual flower is only about 1/8 inch long with a 5-toothed yellow-green calyx and around 6 to 8 stamens, no petals. The female flowers (pistillate) are also in drooping clusters, but shorter, 1 to 2 inches long. They are the same size and color as the male flowers but with a two-carpel ovary with styles. Both flowers appear with the leaves and when monoecious, can be together in the same cluster. Flowers are wind pollinated.

Seed: Female flowers mature to two one-seeded samaras, about 1 inch long, with a broad wing; the samaras are paired forming an angle of 45 to 90 degrees, green initially and turning light brown. These mature in late summer, drop from the tree in the autumn and are wind dispersed. It usually takes 30 to 40 years for a tree to produce a quantity of seed.

 

Habitat: Black Sugar Maple grows in moist to mesic soils that are well drained, full sun to light shade. The root system is shallow and branching. The foliage is thick and produces thick shade.

Names: The genus, Acer, is the Latin word for 'maple.' The species name, nigrum means 'black.' The author name for the plant classification, ‘F.Michx.’ is for Francois Andre Michaux (1770-1855) French botanist, son of botanist Andre Michaux. He traveled with his father in the United States and his monumental work incorporating his father’s notes was a 3-volume work - The North American Sylva, 1817-1819. Botanists have recently moved the maples into the Sapindaceae family from the older Aceraceae family.

Comparisons: The distinction between the Sugar Maple, Acer saccharum, and the Black Sugar Maple is something botanists like to argue over. The characteristics of the two trees overlap and the sap of both is used for syrup. The bark may be blacker on Black Maple, but not always. The leaf tends to have wavy droopy edges with more taper to the lobes and the lower sinuses are almost closed. The samaras tend to be a bit more divergent. Other than that you may not see the difference.