Black walnut - fall color
black walnut spreading habit when open grown in fall color
Black walnut - twig
twig with three lobed leaf scar and tan fuzzy buds
Black walnut - bud break
with bud break leaves and male flowers emerge
Black walnut - immature leaves and catkins
leaves and catkins (male flowers) elongating
Black walnut - leaves
these pinnately compound leaves are usually missing a terminal leaflet
Black walnut - fall color and fruit
the yellow leaflets fall off individually leaving leaf stems and fruit attached to the twigs

Plant Characteristics:

  • Tree: large tree up to 90 ft or more; develops a straight, clear trunk with a narrow crown under competition in the forest; open grown it has a short trunk and wide crown
  • Bark: dark brown to black; thick, ridged and furrowed with a deep diamond pattern 
  • Twigs: stout, orange brown; leaf scars are 3 lobed, resembling a “monkey face”; chambered pith inside
  • Buds: tan large with a few fuzzy scales
  • Leaves: alternate; pinnately compound; 12 to 24 in long with 10 to 24 narrow pointed, finely toothed leaflets 3 in long; yellow-green above, paler below; typically lacking a terminal leaflet
  • Fall Foliage: yellow
  • Flowers: species has both male and female flowers on the same tree. Male flowers are single stem catkins, 2½ – 5½ in long; female flowers on short spikes near the twig end; yellow-green
  • Fruit type: round, 2 – 2½ in, with a thick green husk containing a furrowed and hard nut with sweet, oily, edible meat; matures in late summer to fall, turning brown to black

Additional Details:

  • The tree produces a chemical called juglone that inhibits growth of other plants beneath it.
  • The wood is prized and durable – used in cabinets, furniture, veneer and gunstocks.
  • The delicious nuts must be gathered early, before squirrels and other wildlife can consume them. 
  • The nuts are used to make flour and oil for cakes and candy. The sap can also be collected and boiled down into syrup.
  • The husks were used by the pioneers as dye and as a metal preservative for traps to keep them from rusting.
  • Ground husks have provided insecticides, fish poison and black dye.
  • The seedling develops a strong taproot and is difficult to transplant.
  • Black walnut is the preferred host of the luna and regal moth.

A member of the Walnut Family.

References:
Brown, R. and M. Brown. 1972. Woody Plants of Maryland. Port City Press, Baltimore, MD.
Foster, S. and J. Duke. 1990. A field guide to medicinal plants of Eastern and Central North America. Houghton Mifflin Company, Boston, MA.
Grimm, W. C. and J. Kartesz. 2002. The Illustrated Book of Trees. Stackpole Books. Mechanicsburg, PA.
Harris, J. and M. Woolf Harris. 1994. Plant Identification Terminology: An illustrated Glossary. Spring Lake Publishing, Spring Lake, UT.
Peterson, L. 1977. A field guide to edible wild plants of Eastern and Central North America. Houghton Mifflin Company, Boston, MA.
Virginia Department of Forestry. 2022. Common Native Trees of Virginia – Tree Identification Guide.
The Wildflower Center Staff. 2023. Plant Database. Lady Bird Johnson Wildflower Center. The University of Texas at Austin.