Identifying characteristics:
The swamp white oak has a straight trunk with a broad, open, rounded crown.
The upper branches are stout and ascending, the lower branches drooping.
Trees may live more than 300 years, reaching a height of 60 to 70 feet (occasionally
115 feet). The leathery, shallowly lobed leaves
are simple, alternate, and 5 to 7 inches long. The midrib and petiole are
often yellowish. Leaf surfaces are dark green above and silvery-white and
finely hairy below. The term "bicolor" refers to the contrasting
color of the top and bottom leaf surfaces, but some other oaks, like the
bur oak, share this two-tone trait. Fall color is yellow to purplish-red.
Male and female flowers occur
in separate catkins on the current year's growth. Male flowers are in slender,
greenish-yellow, drooping, 3- to 4-inch-long catkins and the tiny female
flowers are in clusters of 2 to 5 on a short stalk. The shiny, light brown,
ovoid acorns are about 1 inch long,
and are usually paired at the end of a 1- to 4-inch-long stalk. Acorns are
shed in September and October, with large crops produced every 3 to 5 years.
A bowl-shaped cup covers the lower one-third of the nut. Cup scales are
slightly thickened and along the rim upward-pointing scales form a fringe.
The light chestnut-brown, imbricate buds are nearly round and are
coated with fine down above the middle. Bark
is gray-brown and thick, with deep, longitudinal furrows separating broad,
flat, blocky, ridges.
Similar species:
Ecology:
Distribution: This oak is native from Quebec to Georgia, west
to Arkansas and Michigan. It occurs as scattered trees in eastern and central
Iowa, and occasionally as the dominant species in bottomland savannahs in
south central Iowa.
Habitat: Often found at swamp edges, in low flats or bottomlands, and along stream banks, this species can withstand heavy, poorly-drained soils. It is considered to be easier to transplant than white oak (Q. alba) and can withstand drought. Like many other oaks, it is susceptible to iron deficiency chlorosis.
Uses:
Wood: The wood is not distinguished from white oak in commerce.
It is tough, strong, hard, heavy, durable and close-grained. Its
scarcity and relatively knotty wood (lower branches retained for years)
reduce the importance of this species as a timber tree. The wood is used
for general construction, cabinets, veneers, and interior finishes. Its
strength and hardness make it suitable for use as mine timbers and cross
ties. The heartwood is light brown and the sapwood very similar in color.
Wildlife: Wood ducks, mallards, turkeys, woodpeckers, squirrels, small rodents and deer feed on the sweet acorns.
Horticulture: The white swamp oak is an attractive shade tree for large areas where the soil is not too alkaline.
