Bitternut Hickory
Common Names: Swamp Hickory, Yellowbud Hickory
Scientific Name: Carya cordiformis (Wangenh.) K. Koch
Family: Juglandaceae (Walnut Family)
Native Range: Eastern North America; southern Ontario and southern Quebec in Canada; widespread across eastern U.S.
Size & Growth
Typical Height: 18–25 m
Maximum Height: ~30 m
Trunk Diameter (Average): 30–50 cm
Maximum Trunk Diameter: ~100 cm
Growth Rate: Medium
Lifespan: 150–200 years
Record Age: ~250 years
Crown Form: Straight trunk, narrow crown
Shade Tolerance: Moderate (more tolerant than most hickories)
Leaves
Length: 12–25 cm (entire leaf)
Structure: Pinnately compound, 7–11 lanceolate leaflets
Color: Dark green above, paler and slightly hairy below
Unique Features: Bright sulfur-colored buds
Bark
Young Trees: Smooth, greenish-gray with pale vertical lines
Mature Trees: Dark grey with shallow, narrow scaly ridges
Flowers & Reproduction
Flower Type: Monoecious (male and female flowers on same tree)
Male Flowers: Drooping catkins, ~8–10 cm long
Female Flowers: Short spikes near twig ends
Pollination: Wind
Seed Maturity: Autumn of same year
Seed Production: Every 2–3 years (mast years)
Fruit/Nuts:
Shape: Globular, pointed tip, subglobose
Size: 20–35 mm (2–3.5 cm)
Husk: Thin, splits into 4 sections
Kernel: Extremely bitter; largely inedible to wildlife
Dispersal: Gravity; limited animal dispersal
Site Requirements
Soil Preferences: Moist, fertile, well-drained loams; tolerates clay, alluvial, and poor soils
Water Needs: High; prefers very moist sites; sensitive to drought
Climate: Canada Zones 4–7; USDA Zones 4–8
Light: Full sun to partial shade
Disturbance Ecology
Fire Resistance: Low
Fire Regeneration: Poor; regeneration primarily from seed
Vegetative Reproduction: Root and stump sprouts common; prolific compared to other hickories
Rooting Habit
Deep taproot with laterals emerging at right angles
Dense root system; highly windfirm and transplantable
Root development supports survival in adverse conditions
Wood Properties
Strength: High
Decay Resistance: Low
Uses: Tool handles, sports equipment (e.g., lacrosse sticks), fuelwood, smoking wood
Pest/Disease Resistance: Moderate; susceptible to hickory bark beetles, nut weevils, and various fungi
Ecological Role
Component of mixed hardwood forests; contributes to canopy structure
Nuts rarely eaten due to bitter taste; bark may be consumed by small mammals
Associated species: oaks (Quercus spp.), sugar maple, basswood, green ash, shagbark, pignut hickories, dogwood, pawpaw, and various understory shrubs and herbs
Cultural & Historical Notes
Wood valued for toughness and shock resistance
Seeds historically roasted as a coffee substitute (not recommended due to bitterness/toxicity)
Most widespread hickory in Canada
Conservation & Threats
Sensitive to drought and flooding
Habitat loss and competition from invasive species
Seed predation limits natural regeneration
Prolific sprouting allows resilience under some environmental pressures
Sources:
Ontario.ca – Bitternut Hickory
USDA Forest Service – Carya cordiformis
H. Clay Smith, Bitternut Hickory, USDA
Society of American Foresters, Forest Cover Types and Species Associations