
Fagaceae (oaks)
Black oak is a medium-sized tree with a wide-spreading, open crown and tall, straight trunk.
Leaves are alternate, simple, with 5–7 bristle-tipped lobes, cut deep or shallow. They are 5–10 inches long, 3–8 inches wide, dark and shiny above, pale and conspicuously fuzzy underneath (the species name, velutina, means "velvety").
Bark is smooth on branches, becoming black and very rough. The inner bark is distinctively mustard yellow or orange, and bitter.
Twigs stout, reddish-brown, hairy at first, smooth with age. End buds sharp-pointed, distinctly angled, covered with gray hairs.
Flowers April–May, in catkins.
Fruits September–October. Acorns solitary or in pairs, reddish-brown, striped, oval with a rounded tip, ½ to 1 inch long. Cup with inner surface and scale edges hairy; deep, covering acorn halfway. Acorns ripen in autumn of second year.
Height: to 85 feet; spread: to 85 feet.
Occurs naturally on rocky, sandy, or dry upland ridges and slopes; also on sandstone, chert, or igneous glades and along borders of woods and fields. Cultivated, it grows on a great variety of sites and will reach commercial saw-log size on almost every soil type, but it is slow-growing and lacks the brilliant fall color that some other oaks have.
Black oak and scarlet oak are both relatively short-lived (less than 120 years). When old-growth shortleaf pine was logged from the Ozarks from 1890 to 1920, scarlet and black oak colonized those lands. Recently these oaks have been declining, and public land managers are working to restore those areas to the original pine woodlands, currently one of our rarest forest communities.
Black oaks can be used in landscaping and windbreaks, and their wood becomes rough lumber and many wood products, including flooring, pallets, railroad ties, and bridge timbers. Historically, Native Americans used oaks to make a wide variety of medicines. Famed botanical author Donald Culross Peattie pointed out that, "as a forest tree, as part of the hard, untamed, original sylva," black oak "has a rough, unbending grandeur of its own."
A consistent producer of acorns, black oak feeds blue jays, woodpeckers, wild turkey, ruffed grouse, bobwhite, mice, squirrels, raccoons, and deer. Many types of animals find homes in its strong branches and in hollow places in the trunks; more inhabit it after the tree falls.
There are no sharp dividing lines between trees, shrubs, and woody vines, or even between woody and nonwoody plants. “Wood” is a type of tissue made of cellulose and lignin that many plants develop as they mature — whether they are “woody” or not. Trees are woody plants over 13 feet tall with a single trunk. Shrubs are less than 13 feet tall, with multiple stems. Vines require support or else sprawl over the ground.