Plant
Blackjack Oak
Quercus marilandicaAlso known as Barren Oak, Black Oak, Jack Oak
Blackjack oaks thrive on poor, dry, acidic soils where other hardwoods struggle, forming stunted, gnarled silhouettes across barrens and open savannas. Thick, blocky, near-black bark helps them withstand periodic ground fires, while broad, leathery, three-lobed leaves minimize moisture loss in baking heat. Their bitter acorns take two seasons to mature, providing a critical winter food reserve for wild turkeys, deer, and small rodents.
Drought-TolerantFire-AdaptedDeciduous
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Diet & preySunlight, Water, Soil Nutrients
Predators
- White-tailed Deer
- Wood-boring Beetles
- Oak Wilt Fungus
ThreatsFire suppression, land clearing, oak wilt, and invasive pests
HabitatsDry rocky uplands, pine-oak barrens, sandy savannas, and scrub forests
Life span80–150 years
Classification
- OrderFagales
- FamilyFagaceae
- GenusQuercus
- SpeciesQuercus marilandica
Range data is not available yet.
Interaction riskHigh
- Low
- Moderate
- High
- Very high
- Why interaction risk is high
- Acorns and leaves contain tannins toxic to dogs and livestock if ingested; harmless to observe.
Responsible observation
- Bark Identification: Look for rough, deeply furrowed bark divided into dark, rectangular plates resembling charcoal briquettes.
- Foliage Inspection: Note the heavy, club-shaped leaves with three shallow, bristle-tipped lobes and rusty fuzz underneath.
- Habitat Clue: Find them marking dry, nutrient-poor sites such as serpentine barrens or sandy ridges where few trees grow tall.
Frequent Companion Larry D. Moore / CC BY 4.0 · cc-by
Same Genus (c) Trevor Edmonson, some rights reserved (CC BY) · cc-by
Same Genus (c) hr_dragonfly, some rights reserved (CC BY), uploaded by hr_dragonfly · cc-by
Frequent Companion Sandysphotos2009 / CC BY 2.0 · cc-by
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