Overcup Oak
Quercus lyrata
A tough white oak of southern river bottoms, increasingly used as a durable, clean urban street tree for its tolerance of wet clay, drought, and compaction once established. Named for acorns almost fully enclosed by their caps; slower than red oaks but well-structured and long-lived.
Field reference
Family
Fagaceae
Growth rate
Slow
Mature size
40–60 ft tall, 40–60 ft spread
Hardiness zone
5–9
Soil preference
Wet, heavy clay bottomlands; tolerates flooding and poor drainage better than most oaks
Sun
Full sun
Pruning window
Mid-winter (dormant); avoid spring wounds in oak-wilt zones
Wood properties
Strong, durable white-group oak (~0.62 SG) sold with white oak. Sound limbs; tolerant of wet sites, with acorns nearly enclosed by the cap (the 'overcup').
Native range
Southeastern and south-central United States bottomlands, Delaware to Texas
Green weight
62 lb/ft³
Pests & diseases to watch
Common questions
Is overcup oak a good street tree?
Increasingly, yes — it tolerates wet clay, occasional flooding, drought, and compacted urban soil, keeps a strong central leader, and stays relatively clean, making it a tough, adaptable choice where many oaks struggle.
What makes the acorns unusual?
The cap nearly or completely encloses the acorn — the 'overcup' — which helps the buoyant nuts float and disperse in the floodwaters of its bottomland habitat.
Related species in Fagaceae
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