Height: To 30 feet in natural habitats; sometimes twice as tall when cultivated
Evergreen/Deciduous: Deciduous
Lifespan: Slow-growing and likely reaches or exceeds 200 years
Fall Foliage: Unimpressive yellowish brown.
Range: Throughout the eastern U.S., as far west as precipitation allows (well past the Mississippi River)
Typical Habitat: This is a tree of dry, rocky, often upland areas
The Post Oak: A Rugged Survivor
One of the most notable aspects of the post oak is its ability and tendency to live in somewhat inhospitable areas.
But while it tolerates dry conditions and the trials and tribulations of living in exposed areas, it “shows” this hard lifestyle in its growth habit – the post oak is typically small (but clearly a tree) with gnarled branches.
It lacks the attractive canopy silhouette of the pin oak (Quercus palustris) or the ancient aesthetic of the white oak (Quercus alba). It just isn’t a “pretty” tree.
Accordingly, the post isn’t often planted as a landscape tree, and its height, spread and growth habit make it a relatively poor shade tree.
Identification: Tips & Tricks
There are a couple of other oaks that sometimes produce leaves that vaguely resemble the blackjack oak. But the most likely species you’d confuse them with is the southern red oak (Quercus falcata). But, if you can sample several leaves, you’ll usually be able to distinguish the flat-across-the-tip tendency many blackjack oaks exhibit from the curved apex lobes of the southern red oak.
The : Additional Information
Want more info about the blackjack oak? Check out some of these great resources:
- U.S. Forest Service: A comprehensive resource covering everything from taxonomy to fire ecology.
- Illinois Wildflowers: A nice resource; state-specific, but broadly applicable.
- Missouri Department of Conservation: An accessible, field-guide style page covering the blackjack oak.