(Acer saccharum Marshall)
Sugar maple is a deciduous tree, alternatively known as hard or rock maple, and is a member of the soapberry family (Sapindaceae, previously Aceraceae)¹. The tree typically reaches a height of 40 to 80 feet (maximum 120 feet) and can live 400 years1,2. The five-pointed leaves are attached on opposites sides of the stem and are palmately veined (all the principal veins meeting at the base). The leaf blades are 3-6 inches long and are smooth edged except for a few pointed teeth on lobes. The leaf of a sugar maple is bright green in the spring and summer, and turns red, orange, or bright yellow in the fall. Flowers are inconspicuous and green in clusters of 9-14. The fruit of a sugar maple is a pair of samaras, commonly known as “helicopters,” each about one inch long and used to carry the seeds down to the ground in a spiral path when they are shed in the fall¹. The tree flowers from April-June, and fruits from September-October.
Sugar maple leaf. Superior National Forest. Wickimedia Commons³
Sugar maple samara. University of Richmond4
Sugar maple is distributed from Nova Scotia, west across southern Canada to Manitoba, south through Wisconsin to Missouri, and and northeast along the Appalachian Mountains through New Jersey and into New England¹. In Maryland it occurs primarily in Western Maryland and scattered in the Piedmont5. As a native, it is absent from the coastal plain, but is widely planted. It grows in moist, well-drained, slightly acid soils².
Native range of sugar maple. USDA¹
Native populations of white-tailed deer, snowshoe hares, red and gray squirrels, and flying squirrels eat the leaves, seeds, and buds of the sugar maple tree. Bees and other pollinating insects commonly visit the flowers of a sugar maple tree¹. Porcupines can eat the bark, and most native bird species (including woodpeckers and songbirds) nest in the tall branches of the tree¹.
In the United States, sugar maple from this tree is the only kind used for commercial production of maple syrup¹. This is because the maple from a sugar maple has twice the amount of sugar than other maple trees (hence the name ‘sugar maple’). It takes 40 gallons of sap to produce one gallon of maple syrup. Production of maple syrup can be for commercial purposes or as a hobby6. The timber of sugar maple trees is hard and heavy, making it a strong industrial wood. Sugar maple timber is used to make furniture, flooring, and paneling, as well as tool handles, sporting goods, musical instruments, baseball bats, and bowling pins¹. Additionally, landscapers often choose the sugar maple tree for ornamental purposes, because the crown of the tree provides good shade coverage on sunny days and the excellent fall colors.
The sugar maple is a generally stable tree, however there are some notable threats to the species. The sugar maple does not tolerate compacted soil conditions, extremely high heat, air pollution, and road salt¹. Because of this, they are not planted as street trees. If grown in swampy areas with poorly drained soil, the sugar maple is susceptible to a fungal disease called verticillum wilt that may cause tree death¹. A recently observed phenomenon called “maple decline” has occurred in the Northeast US sugar maple populations, where large groups of large sugar maples die due to acid rain and high air pollution¹.
- The Maryland State Champion sugar maple is 82 ft tall and 60 in in diameter and located in Carroll County7.
- Maple sugar production in the USA for 2020 was 4.4 million gallons from 13.5 million taps at a wholesale price of $31.00 per gallon8.
- Demonstrations of maple syrup production can be seen at Cunningham Falls State Park9 and at Oregon Ridge County Park10 each February.
- USDA-Forest Service Silvics Vol. 2 Hardwoods: Acer saccharum
- Missouri Botanical Garden: Acer saccharum
- Wikimedia Commons: Acer saccharum
- University of Richmond–Faculty Staff.
- Maryland Plant Atlas, Sugar Maple
- Penn State Extension: Maple syrup production for the beginner
- Maryland State Champion Trees
- Maryland Department of Natural Resources: Golden anniversary for Cunningham Falls maple syrup festival
- Oregon Ridge Nature Center: Maple sugar weekdays and weekends
Contributed by K. Brunner