Got Nature? Blog

The full publication is available for download for $7 in the Purdue Extension Education Store. The field guide helps identify common Indiana woodlot trees.

Each week, the Intro to Trees of Indiana web series will offer a sneak peek at one species from the book, paired with an ID That Tree video from Purdue Extension forester Lenny Farlee to help visualize each species as it stands in the woods. Threats to species health as well as also insight into the wood provided by the species, will be provided through additional resources as well as the Hardwoods of the Central Midwest exhibit of the Purdue Arboretum, if available.

This week, we meet Black walnut or Juglans nigra.

Also known as American black walnut or eastern black walnut, this species has compound leaves with several pairs of leaflets along the individual leaf stems. The leaves, which are arranged alternately on the twigs, can be between one to two feet long. They are green in summer and turn yellow in the fall. The terminal and lateral buds are fuzzy and tan and can resemble suede.

The bark has long, strong running ridges and in older trees can resemble alligator hide. Under the surface of the bark is a dark, chocolate brown color.

Black walnut trees produce nuts, which are ridged and rounded with very heavy shells. Nuts are encased in a thick yellow-green husk, which can leave a dark brown stain on skin. The nut shells require a heavy hammer hit or sharp animal teeth or claws to break open. The nut meat has a very strong aromatic flavor.

Black walnuts, which grow 50 to 75 feet tall, prefer to grow in sunshine and in high quality soils that are deep and well-drained. This species is often found as one of the tallest in the woodlands where they grow. The best quality trees are frequently found on flood free ledges just above stream banks. This species will live on poorer soils, but growth is slow and the wood quality is generally poor.

The natural range of the black walnut is the from the east coast west through the Great Plains. It ranges from Texas and Georgia north to central Minnesota, Wisconsin, Michigan and southern Ontario.

For full article with additional photos view: Intro to Trees of Indiana: Black Walnut, Forestry and Natural Resources’ News.

If you have any questions regarding wildlife, trees, forest management, wood products, natural resource planning or other natural resource topics, feel free to contact us by using our Ask an Expert web page.

Other Resources:
ID That Tree: Black Walnut
Hardwoods of the Central Midwest: Black Walnut
Hardwood Lumber and Veneer Series: Black Walnut
Morton Arboretum: Black walnut
Thousand Cankers Disease: Indiana Walnut Trees Threatened, The Education Store
Facts About Black Walnut, The Education Store
Purdue Arboretum Explorer
Black Walnut, Native Trees of Indiana River Walk, Purdue Fort Wayne
The Woody Plant Seed Manual, U.S. Forest Service
Fifty Trees of the Midwest app for the iPhone, The Education Store
Native Trees of the Midwest, The Education Store
Shrubs and Woody Vines of Indiana and the Midwest, The Education Store
Investing in Indiana Woodlands, The Education Store
Forest Improvement Handbook, The Education Store
ID That Tree, Purdue Extension-Forestry & Natural Resources (FNR) YouTube playlist
Woodland Management Moment , Purdue Extension-FNR YouTube playlist

Wendy Mayer, FNR Communications Coordinator
Purdue University Department of Forestry and Natural Resources

Lenny Farlee, Sustaining Hardwood Extension Specialist
Purdue University Department of Forestry and Natural Resources