Bur Oak
Thick bark and an enormous root system let bur oak stand where prairie fire, drought, and winter test less durable trees.
Artwork inspired by Birger Sandzén
The acorn cup’s shaggy fringe gives this oak both its common name and its quickest field mark. Mature trees build massive limbs and deeply ridged bark; their acorns provide concentrated autumn food for deer, turkeys, squirrels, and many smaller animals.
Confirm several leaves because their lobing varies dramatically, and admire veteran trees without climbing or compacting the soil beneath their canopies. Search old homesteads, riparian woods, and prairie openings for isolated spreading crowns. Acorns September–October.
- Best clue
- Broad-crowned oak with very large acorns enclosed by fringed cups
- Habitat
- prairie groves, stream valleys, savanna, and upland woodland edges
- Regional status
- Native prairie-border oak
Quick guide
- Overall clue
- Fringed acorn cup
- Then confirm
- Variable lobed leaves
Read Bur Oak from whole plant to detail
- Read the silhouette
- Begin with the opening test is broad-crowned oak with very large acorns enclosed by fringed cups.
- Check another feature
- Look for fine detail should add information: verify huge spreading crown and, when visible, deep corky bark together with variable lobed leaves before accepting the identification.
- Use habitat carefully
- Prairie groves, stream valleys, savanna, and upland woodland edges; acorns September–October.
- Keep behavior natural
- Use more than one branch of Bur Oak for comparison because leaf shape and exposure can vary within a crown.
Good to know
The shaggy acorn cup supplies the name, while massive limbs, thick bark, and variable leaves reflect a long-lived oak adapted to prairie edges and fire.
Notice these
- Fringed acorn cup
- Huge spreading crown
- Deep corky bark
- Variable lobed leaves