Tree · Juglandaceae
Black walnut
Juglans nigra
Black walnut is recorded as native to 33 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 1,279 counties of those states by USDA PLANTS.
Key facts · USDA PLANTS
Black walnut at a glance
- Native in
- 1,279 counties, across 33 states and territories
- Estimated cold hardiness
- Zone 4b PLANTS minimum temperature −28°F
- Mature height
- 100 ft PLANTS mature height
- Light and water
- Full sun (shade-intolerant) High water use
Estimated cold hardiness: zone 4b. PLANTS gives a minimum temperature of −28°F; zone 4b winters bottom out at −25°F, the coldest half-zone that stays within that limit.
Black walnut is recorded as native to 33 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 1,279 counties of those states by USDA PLANTS.
Counties where it is native
The 15 counties with the most ZIP codes among the 1,279 where it is listed.
Native counties by state
- Alabama 37 counties
- Arkansas 69 counties
- Connecticut statewide record
- Delaware 2 counties
- District of Columbia 1 county
- Florida 7 counties
- Georgia 24 counties
- Illinois 101 counties
- Indiana 55 counties
- Iowa 20 counties
- Kansas 80 counties
- Kentucky 108 counties
- Louisiana 38 counties
- Massachusetts 5 counties
- Michigan 27 counties
- Minnesota 25 counties
- Mississippi 21 counties
- Missouri 113 counties
- Nebraska 26 counties
- New Jersey 19 counties
- New York 38 counties
- North Carolina 51 counties
- Ohio 88 counties
- Oklahoma 30 counties
- Pennsylvania 50 counties
- Rhode Island 2 counties
- South Carolina 16 counties
- South Dakota 4 counties
- Tennessee 42 counties
- Texas 23 counties
- Virginia 89 counties
- West Virginia 41 counties
- Wisconsin 27 counties
Growing traits
Values from the PLANTS characteristics record. “Not recorded” means PLANTS has no value; nothing here is estimated except the zone.
Growth
- Growth habit
- Tree
- Duration
- Perennial
- Mature height
- 100 ft
- Growth rate
- Rapid
- Growth form
- Single Stem
- Shape
- Erect
- Lifespan
- Moderate
- Active growth period
- Spring
Light and water
- Shade tolerance
- Intolerant (full sun (shade-intolerant))
- Moisture use
- High water use
- Drought tolerance
- Low
- Tolerance of waterlogged soil
- None
- Precipitation range
- 30 to 60 in per year
Soil
- Soil textures
- Medium
- pH range
- 4.6 to 8.2
- Lime (CaCO₃) tolerance
- High
- Salinity tolerance
- None
- Fertility requirement
- High
- Minimum root depth
- 40 in
Climate
- Minimum temperature
- −28°F
- Estimated cold hardiness
- Zone 4b and warmer
- Minimum frost-free days
- 170
- Fire tolerance
- High
Flowers, leaves and fruit
- Flower color
- Yellow
- Showy flowers
- No
- Bloom period
- Late Spring
- Foliage color
- Green
- Showy in fall
- No
- Keeps leaves
- No
- Fruit color
- Brown
Other
- Toxicity
- Slight
- Nitrogen fixation
- None
- Nursery availability
- Routinely Available
- Family
- Juglandaceae
- PLANTS symbol
- JUNI
Source & data date
- Source
- USDA NRCS PLANTS Database: county distribution records, native status and plant characteristics. CC0 (public domain dedication, per the data.gov catalog record).
- Kew’s World Checklist of Vascular Plants (WCVP): native or introduced status by state. CC BY 3.0.
- USGS US-RIIS (ver. 2.0): species listed as introduced are excluded. CC0.
- Citation
- USDA, NRCS. 2026. The PLANTS Database (https://plants.usda.gov, 11/04/2026). National Plant Data Team, Greensboro, NC USA.
- Govaerts R. (ed.) (2026). WCVP: World Checklist of Vascular Plants. Facilitated by the Royal Botanic Gardens, Kew. Data file dated 2026-06-04, http://sftp.kew.org/pub/data-repositories/WCVP/ (retrieved 2026-11-04). Paper: Govaerts R. et al. (2021) The World Checklist of Vascular Plants, a continuously updated resource for exploring global plant diversity. Scientific Data 8, 215.
- Data date
- Retrieved from PLANTS on November 4, 2026; WCVP data file dated June 4, 2026.
- Scope
- Juglans nigra (PLANTS symbol JUNI).
- Method
- A species is listed when it is recorded as native to the state in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in the county by USDA PLANTS. Species PLANTS labels both native and introduced are listed separately. Full method · All sources