Black Walnut
Juglans nigra
Last reviewed: June 2026
Black Walnut is toxic to dogs.
Listed as toxic by the ASPCA Animal Poison Control Center (last reviewed 2026-05-21). If your pet has been exposed, call the ASPCA Animal Poison Control Center at (888) 426-4435and your veterinarian's emergency line.
Pollinator Patch flags toxic plants so you can choose a pet-safe native alternative for your yard.
Light
part shade
Water
medium
Size
300"–600" H × 300"–600" W
Bloom
May, Jun
Native to
AL, AR, CT, DE and 29 more states
Pollinators
bees, beetles
Browse plants for this ecoregion
Black walnut is a large native shade tree that can reach 25-50 feet tall with an equally wide canopy. It produces edible nuts in fall and has distinctive compound leaves that turn yellow in autumn. The tree is allelopathic, meaning it releases chemicals that can inhibit the growth of many other plants nearby.
In an HOA neighborhood
Black Walnut takes more care to keep looking intentional in a front yard. Maintenance level: high. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Extremely large size inappropriate for most residential lots
- Drops messy nuts and leaves requiring constant cleanup
- Allelopathic properties can damage nearby ornamental plants
Wildlife value
Host plant for luna moth, viceroy butterfly, banded tiger moth.
Black walnut supports bees and beetles during its spring bloom period. The nuts provide food for squirrels, chipmunks, and other wildlife throughout fall and winter.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Pollinator Patch flags toxic plants like Black Walnut and shows pet-safe natives for your ecoregion instead.