Blackjack Oak Tree Leaves
Posted By admin On 14/04/22I highly doubt blackjack oak is hardy to zone 3, its pretty much a zone 6 oak. Neutral: On Nov 27, 2006, QueenB from Shepherd, TX (Zone 8b) wrote: Often found here in East Texas growing with Southern Red Oaks and Post Oaks. The leaves do resemble Water Oaks to a degree, but are larger and wider, and the bark is nearly black on mature trees. Get ready for variability! Tree leaves may vary in size on the same tree. Leaves growing in the shade are often much larger than leaves exposed to full sun. Some trees may have more than one leaf shape growing on the same tree. Learn bark characteristics and tree shape as quickly as possible. Leaves are not present on many trees at least.
- Natural History
- Identifying Characteristics
- Images
Natural History
Leaves and branch of bluejack oak
Photo credit: Larry Korhnak, University of Florida
As the common name implies, the primary distinguishing feature of bluejack oak is the blue hue of the leaves. It also has a single bristle on the tip of the leaf. This is a characteristic that separates 'red' oaks (with bristle tips) from 'white' oaks. It ranges from southeastern Virginia to central Florida and as far west as southeastern Oklahoma and central Texas. Neighboring trees in its pine sandhill and hardwood hammock habitats include longleaf pine, turkey oak, southern red oak, and common persimmon.
The acorns are extremely valuable to wildlife such as deer, raccoons, squirrels, and quail. Sherman's fox squirrel prefers to consume bluejack oak acorns to other acorns, suggesting the acorns of this species taste better. Because this tree is often small and becomes a dense thicket, it provides important shelter and nesting sites for wildlife.
Bluejack oak is rarely used for timber, but it is an excellent wood for fuel, fence posts, and barbecue. It has also been used as pulpwood for making paper.
Blackjack Oak Tree Leaves Pictures
Identifying Characteristics
| Habitat: | Bluejack oak grows on well-drained sandy soils in pine sandhill and dry hardwood hammock communities. |
| Size/Form: | Bluejack oak is a small tree that only reaches heights of 30' to 50'. It is often shrubby, with an irregular crown and short, crooked trunk. |
| Bark: | The grayish black bark is thick with blocky furrows and rough ridges. |
| Leaves: | The leaves are simple, alternately arranged, and may persist on the tree until spring. The leaves are 3' to 5' long by ½' to 1' wide. The oblong or narrowly elliptical shaped leaves usually have a bluish gray, leathery upper surface. The underneath surface is whitish gray with wooly fuzz. The leaf base and tip are rounded, but there is a single, prickly bristle on the tip. The margin is smooth. |
| Fruit: | The acorns are ½' to ¾' long. The cap covers 1/2 to 1/3 of the acorn. Acorns mature in two growing seasons. |
Images
Click on thumbnails to see a larger image in a new window. Close the new window to return to this page.
| Bark | Acorns | Insect gall on twig | Leaves, showing the upper and lower surfaces |
| Photo credit: Larry Korhnak, University of Florida | Photo credit: Larry Korhnak, University of Florida | Photo credit: Larry Korhnak, University of Florida | Photo credit: Larry Korhnak, University of Florida |
Learn More
Blackjack Oak Tree Leaves Pictures
- About the Contest
- Contest Stations