Wednesday, October 17, 2012

Black Walnut

A cluster of 2 Black Walnuts
This weekend’s high winds knocked many of the Black Walnut (Juglans nigra) out of the trees and prompted me scurry around like a squirrel and stash a bunch of nuts for the winter. Continuing in the vein of last month’s posts on Manchurian Walnut (Juglans mandshurica) and Japanese Walnut (Juglans ailantifolia var. cordiformis), I thought I would start with a detailed description of the species.

Deep braided fissures of Black Walnut bark
Notice the fine hairs in the vein axils
Black Walnuts are the largest of 6 species of walnut that are native to North America, often reaching 130 feet tall. They are frequently planted outside of their native central and eastern US range, and it not uncommon to find them scattered throughout our region, especially east of the Cascades next to farmhouses, and in parks and yards. Black Walnuts have brownish grey bark with braided fissures. Twigs are also brownish grey with sporadic small lenticels and heart shaped leaf scars. The pinnately compound leaves are 8 to 24 inches long with slightly hairy petioles, especially near the base. Each leaf usually has 15 to 19 lanceolate leaflets that range from 2-6 inches long and roughly ¼ as wide. The terminal leaflet is very small and sometimes absent. Leaflets are often slightly curved and have serrated margins; the upper surfaces are smooth except for small scattered hairs on the veins, and lower leaf surfaces are minutely hairy, but more conspicuously so at the axils of the leaf veins. Fruits are spherical, 1.5-3 inches wide, and are typically found in clusters of 1 or 2 but sometimes in groups of 3. 

According to the US Forest Service Silvics Manual, Black Walnuts do not produce heavily until they are over 20 to 30 years old, at which point you can anticipate good nut crops 2 out of every 5 years. They fall in September and October about the same time as leaf drop, and I think they look like small green tennis balls before their hulls blacken and shrivel.

Several bags worth of walnuts in a pile
I have never been able to collect Black Walnuts in very large quantities, but this year I found an irresistible tree only 3 blocks away from my house that had dropped a thick layer of walnuts all over the street and sidewalk. I grabbed a large paper bag and my camera and headed down the street to pick. 5 minutes later, my bag was full! I dumped it out in a pile and filled it up again… and again… and again. In just a few hours, I could have easily filled my pickup truck with walnuts from just one tree if I had permission from all the adjacent landowners and if all the walnuts were on the ground.

The husks break off easily when you stomp on them.
Already having more than a year’s supply, I stopped collecting and started processing. I spread the walnuts out on the concrete and stomped on them to break open their green husks and reveal their fissured walnut shells. The husks are very resinous and quickly stained my hands, shoes, and anything else that touched them, an iodine color. I spread my Black Walnuts out on baking sheets to slowly dry in the shell. In a few months, I will crack them with a hammer and do a taste comparison with the other species of walnuts that I have been fortunate enough to collect this year.

After removing the husk I lay my walnuts on a baking sheet to dry
Husk, shell, and nutmeat comparison for 3 species of walnut

Pin It submit to reddit


  1. do you crack them with those channel locks?

  2. The Black Walnut shells are so thick that they would probably break an ordinary nutcracker, and I've heard a hammer is faster. I do crack a lot of nuts with those channel locks, but I will probably use a hammer when I crack the bulk of my Black Walnuts.

  3. Great post!
    Thanks to your info I just realised that in a park near my home there are a couple of Black Walnut trees...
    I live in Barcelona Spain :)

  4. making a tincture from the hulls helps kill parasites in the body

  5. Will they grow in Zone 8 or 9 (the Gulf Coast?)

  6. I can't speak from experience on the matter but the Arbor Day Foundation says they grow in USDA hardiness zones 4-9.

    1. They grow just fine in northern Wisconsin as I have one, and I have heard them being grown in eastern Canada

  7. Luteolin supplements is sometimes called as flavonoid that exists in many types of plants including fruits, vegetables, and medicinal herbs. From here:

  8. Did you know that you can shorten your urls with AdFly and make cash from every visit to your short urls.

  9. Great article – Impressive: We think you might be interested to know more about our company. Techno Data Group helps you get your hands on world’s best class customized B2B Contact List, which can make your sales and marketing campaigns cost effective. Achieve Your Marketing Goals and Grow Your Business.Food and Kindred Manufacturing Email List

  10. There is shocking news in the sports betting world.

    It's been said that any bettor needs to look at this,

    Watch this or quit betting on sports...

    Sports Cash System - SPORTS BETTING ROBOT