Horticulture/Acer saccharum

Ecology
The Sugar Maple is an immensely important species to the ecology of many forests in North America. Pure stands are common, and it is a major component of many forest types. It often forms associations with the American Beech, forming the beech-maple forest type, common in northern areas. Other associations include Sugar Maple-Yellow Birch (which is most important beyond the northern limit of beech), Sugar Maple-American Basswood, Sugar Maple-White Ash and Sugar Maple-Ironwood-Red Oak. Sugar Maples engage in hydraulic lift, drawing water from lower soil layers and exuding that water into upper, drier soil layers. This not only benefits the tree itself but also many other plants growing around it. Sugar Maple is among the most shade tolerant of large deciduous trees. Among North American maples its shade tolerance is exceeded only by the Striped Maple, a smaller tree. Like other maples, its shade tolerance is manifested in its ability to germinate and persist under a closed canopy as an understory plant, and respond with rapid growth to the increased light formed by a gap in the canopy. The sugar maple can grow comfortably in any type of soil, except sand.

Human influences have contributed to the decline of the Sugar Maple in many regions. Its role as a species of mature forests has led it to be replaced by more opportunistic species in areas where forests are cut over. The Sugar maple also exhibits a greater susceptibility to pollution than other species of maple. Acid rain and soil acidification are some of the primary contributing factors to maple decline. Also, the increased use of salt over the last several decades on streets and roads has decimated the sugar maple's role as a "street-front" tree.

In some parts of eastern North America, particularly near urbanized areas, the Sugar Maple is being displaced by the Norway Maple. The Norway Maple is also highly shade tolerant, but is considerably more tolerant of urban conditions resulting in the Sugar Maple's replacement in those areas heavily disturbed by human activities.

Conservation
The sugar maple is widespread, and is considered secure, except at the edges of its range.

Cultivation and uses
The Sugar Maple is one of the most important Canadian trees, being (with Black Maple) the major source of sap for making maple syrup; Sugar Maple being regarded as slightly better. Many maples can be used as a sap source for maple syrup, but none of the others are as good as these two.

The wood is one of the hardest of the maples, and is prized for furniture and flooring. Bowling alleys and bowling pins are both commonly manufactured from sugar maple. Trees with wavy wood grain, which can occur in curly, quilted and "birdseye maple" form, are especially valued. Maple is also the wood used for basketball courts, including the floors used by the NBA, and it is a popular wood for baseball bats, along with white ash.

The Sugar Maple is a favorite street and garden tree, because it is easy to propagate and transplant, is fairly fast-growing, and has beautiful fall color; however, its intolerance of pollution and compacted soils common to inner city conditions make it a frequent victim of maple decline. It also has some of the most dense shade to be found in shade trees. The shade and the shallow, fibrous roots may interfere with grass growing under the trees. Deep well-drained loam is the best rooting medium, although Sugar Maple can grow well on sandy soil which does not become excessively dry. Light (or loose) clay soils are also well known to support Sugar Maple. Poorly drained areas are unsuitable and the species is especially short-lived on flood-prone clay flats. Its salt tolerance is low and it is very sensitive to boron.
 * Cultivars
 * 'Apollo' - columnar.
 * 'Arrowhead' - pyramidal crown.
 * 'Astis' (Steeple®) - heat-tolerant; good in southeastern USA. Oval crown.
 * 'Bonfire' - fast-growing.
 * 'Columnare'
 * 'Fall Fiesta' - tough-leaved, colorful in season, hardy.
 * 'Green Mountain' - durable foliage resists heat and drought.
 * 'Legacy' - tough, vigorous and popular.
 * 'Monumentale' - columnar.
 * 'Newton Sentry' - very narrow.
 * 'Sweet Shadow' - lacy foliage.
 * 'Temple's Upright' - columnar.
 * 'Unity' - very hardy Manitoba cultivar.

Sugar Maple is the State Tree of New York, Vermont, West Virginia and Wisconsin.