Post Oak
Quercus stellata
A rugged, slow-growing white oak of dry uplands with distinctive cross-shaped (stellate) leaves and rounded lobes. Notoriously sensitive to construction — fill, trenching, irrigation, or compaction over its roots kills mature trees, so post oak preservation on building sites is a frequent and high-stakes consulting issue.
Field reference
Family
Fagaceae
Growth rate
Slow
Mature size
35–50 ft tall, 35–50 ft spread
Hardiness zone
5–9
Soil preference
Dry, sandy or rocky, low-fertility soils; extremely intolerant of disturbance, fill, and added water
Sun
Full sun
Pruning window
Mid-winter (dormant); avoid April–July in oak-wilt zones
Wood properties
Dense, hard, rot-resistant white-group oak (~0.67 SG) once split for fence posts. Strong but the dry-site wood is brittle; cross-grained crotch wood resists splitting.
Native range
Central and southeastern United States, Massachusetts to Florida and west to Texas and Kansas
Green weight
62 lb/ft³
Pests & diseases to watch
Oak Wiltfungus · Severe severity · peak Spring and early summer (high infection risk from fresh wounds April–July)Spongy Moth (formerly Gypsy Moth)pest · High severity · peak Caterpillars feed and defoliate May–June; egg masses laid mid-summer overwinterArmillaria Root Rotfungus · High severity · peak Decline visible in summer drought stress; honey mushrooms appear in fall
Common questions
Why is my post oak dying after construction nearby?
Post oak is one of the least disturbance-tolerant North American oaks. Grade changes, trenching, soil compaction, and especially added irrigation over the root zone trigger decline that can show up one to three years later. Protect the entire root area during any construction.
Can I water my post oak during drought?
Be cautious — post oak is adapted to dry, lean soils and is prone to root rot if overwatered, particularly in lawns. Light, infrequent deep watering in extreme drought is safer than routine sprinkler irrigation.
Related species in Fagaceae
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