Black Walnuts (Juglans nigra) are some of the easiest foods to identify and harvest and taste great. The tree’s nuts can be eaten and used in candies and baked goods, like you use other nuts. Foraging for “wild” foods and nuts is part of my Plan B. I grow many berries and vegetables in my garden, including plans for growing “wild” greens. Along with my kitchen garden crops, wild nuts would make a nutritious edition to my diet. Nut trees typically are tall forest trees and I don’t have the space to grow nuts in my small city garden. Foraging is a great answer.
I spotted the Black Walnut trees as I ran errands and made a mental note to return and gather the fallen nuts. I keep a tree location list and notes my cell phone. I’ll use this list to learn what the trees look like in all seasons and to observe how the nuts develop. A reminder in my phone’s calendar for next year, is assurance I’ll start searching at the right time.
Black Walnut Habitat
Black Walnuts are tall trees (110-130 feet) found growing in moist, rich soils particularly soils on floodplains. Its’ growing range includes southern Ontario, west to South Dakota, south to Georgia and east to the Atlantic region.
The tree’s easily worked wood is valued for fuel and woodworking. The trees are grown for both lumber and food.
Black Walnut produces a toxic called ‘jugalone’ which inhibits the growth of plants around it. The largest sources of jugalone are found in the buds, roots, and nut hulls. Signs of jugalone poisoning in plants include leaf yellowing, wilting, and even death. There are plants that can be planted near Black Walnuts and tolerate jugalone. See the Penn State Extension website for a list.
Black Walnut’s Ecosystem Role
Black Walnut is a pioneer tree, growing in disturbed areas, along roads, old fields, and forest edges. Its’ pioneer roles makes it a very common tree in eastern Turtle Island (North America).
The nuts are an important food sources for birds, humans, and other mammals particularly rodents. Squirrels got most of the nuts I gathered. I stored the nuts overnight in a shopping bag on my back balcony. I thought I would get to them early enough in the morning before the squirrels. The squirrels chewed right through the bag.
Black walnut is a host plants for over 100 species of butterflies and moths including the Hickory Hairstreak butterfly, Banded Hairstreak butterfly , Luna Moth, Regal Moth, Imperial Moth, Walnut Sphinx Moth, Fall Webworm Moth, Walnut Caloptilia, Pecan Leafminer Moth, and Monkey Slug Moth.
The Chippewa, Cherokee, Comanche, Iroquois, and Rappahannock use the bark to treat various ailments and as an insecticide. Bark should be used cautiously in medicine, because it is poisonous.
Harvesting Black Walnuts
The foraging books I rely on are by Samuel Thayer. The book I used as a guide to harvesting Black Walnut is Nature’s Garden: A Guide to Identifying, Harvesting and Preparing, Edible Wild Plants. Black Walnuts are profiled on pages 135 -145.
Black Walnuts are the first trees around here to be almost completely bare in autumn. The other trees still have most of their leaves. The Black Walnut’s autumn leaves are gold. Yellowish-green husked nuts hang in groups on the trees. With Black Walnuts, the leaves drop first then the nuts in their thick, fleshy husks. The husks enclose the ripe nuts. The yellowish-green husks smell citrus-y to me. The husked nuts fall to the ground and then turn dark brown.
First I nonchalantly gathered the nuts from beneath a tree on public property that I was pretty sure hadn’t been sprayed with any kind of -cides (pesticides, insecticides, herbicides, etc.).
I have seen squirrels in my neighborhood scampering along with yellowish-green husked walnuts in their mouths. I suspect they gather the freshly fallen yellowish-green husked nuts and then let the tough yellowish-green husk rot to brown. My squirrel neighbors ate all seemed to favor the nuts in soft, rotting dark brown husks. The rotting brown husk easily peels off. The squirrels ate all the brown husked nuts and left the yellowish-green ones in my shopping bag. If humans let the husks rot to dark brown, there is a chance the dark, inky fluid of the husk could seep into the nuts and affect the flavor.
Processing the Nuts
Once home, I used a pocket knife to cut away the yellowish-green husk, removed the nuts, and soaked and rinsed the nuts in a bucket of water. The soaking may not have been needed. I should have dried and cured the nuts. Removing the nut meat from the shell was the next step. I found placing the nuts on a thick piece of scrap wood and whacking the nuts with a hammer worked best for me. The nut meat was easy to remove with a pocket knife or pick.
I didn’t dry or cure the nuts, because I wanted to taste them. I like the taste. From what I’ve read drying and curing the nuts strengthens the flavor. That will have to wait for next year.
I admit I really didn’t know what I was doing. I just followed the directions from the YouTube video above and read Thayer’s book. I hope you find this information helpful. Perhaps, you can add gathering nuts to your Plan B.
Have you been foraging this autumn? Do you have questions about getting started? As always, feel free to leave your thoughts and questions in the comments below. 🙂
Black Walnut Facts
Common name: Black Walnut
Scientific name: Juglans nigra L.
Family name: Juglandaceae (Walnut family)
Description: Black Walnut is a known allelopath. It produces a chemical, called jugalone, which influences the germination and growth of plants growing near it.
Native range: eastern United States, west to southern Minnesota, as far north as southern Wisconsin, south to Texas and the Florida Panhandle
Hardiness Zones: 4-9
Life span: Perennial/Tree. There are specimens 300+ years old.
Growing Black Walnuts
Habitat: fields and rich woodlands; medium textured soils, not tolerate of wet soils
Height: height at 20 years 35 feet and and reach an average height of 70-90 feet tall. Some specimens if left to grow undisturbed can reach 150 feet tall and 8 feet in diameter.
Light needed: Full Sun, doesn’t tolerate shade
Soil/Moisture needed: low drought tolerance
Bloom period: Late spring
Bloom color: Yellow inconspicuous flowers
Leaves; highly aromatic, pinnately compound leaves, which look similar to the leaves of other walnut species, leaves emerge late in the spring
Fruit/Seed Color: brown nuts ripen in the autumn/ fall
Root depth: 40 inches
Starting from Seed: Black walnut is difficult to transplant and should be started from seeds or cuttings in autumn. Seeds do not need cold stratification. Start the seeds in moist, well-drained deep soil rich in organic matter. The plant is not tolerant of drought or shade.
Disease/Problems: As a hostplant for various butterflies and moths expect to find caterpillars. Maggots in the fruit husks but the nuts is unaffected. Canker disease affects the tree.
Uses: Edible nuts, dye form the black husks, fire tolerance, fuelwood, lumber. Bark should be used cautiously in medicine, because it is poisonous. Pruning and Maintenance:
Attracts: Deer will eat the leaves. Squirrels and other rodents eat the nuts.
Host plant to: Black walnut is a host plants for over 100 species of butterflies and moths including the Hickory Hairstreak, Banded Hairstreak, Luna Moth, Regal Moth, Imperial Moth, Walnut Sphinx Moth, Fall Webworm Moth, Walnut Caloptilia, Pecan Leafminer Moth, Monkey Slug Moth.
Juglans nigra on Wikipedia
Landscaping and Gardening Around Walnuts and Other Juglone Producing Plants (Penn State Extension)
A list of book I used for background information. The links open at Amazon.com, of which I am an affiliate. See FAQs: Buying from this website.
Thayer, Samuel. Nature’s Garden: A Guide to Identifying, Harvesting, and Preparing Edible Wild Plants. Birchwood, WI: Forager’s Harvest, 2010.
———. The Forager’s Harvest: A Guide to Identifying, Harvesting, and Preparing Edible Wild Plants. Ogema, WI: Forager’s Harvest, 2006.