Black walnuts usually grow in what is called a riparian zone, which is simply any interface between land and a stream or river, an ecological area found commonly in and around Nevada County due to the various streams and the Little Missouri River. Black walnuts are relatively easy to identify because they have leaves very similar to the pecan tree, though instead of 9-17 leaflets, the black walnut has 16-22 and produces them in even-numbered pairs. The bark of these trees is grey-black and deeply furrowed into ridges which give the bark its characteristic diamond-shape pattern. Also, black walnuts produce allelopathic chemicals that are released from their roots, inhibiting the growth of other plants underneath their canopy, making them undesirable as ornamental plants or in gardens. If the soil biology is rich enough, however, microscopic organisms help remove these chemicals, reducing the allelopathic effect. These compounds are also present in the tree’s leaves and bark, so do not add these to compost piles.
Black walnuts produce somewhat irregularly, with some years having larger crops than others and won’t start fruiting until the tree is from four to six years old. The fruits are round and slightly larger than a golf-ball when they ripen in autumn as a brownish-green somewhat fleshy husks that contain a brown, corrugated nut. The entire fruit falls between October and November and the seed or nut must usually be removed from the husk, this nut being relatively small and very hard. To make harvesting much easier, most foragers will purchase a strong nutcracker, many of which are easy to use because they attach to a table edge and have a large handle. Also, leaving the nuts a few weeks after removing the green husk will allow them to dry and making them slightly easier to crack. Native Americans would use the husks to fish by blocking two ends of a stream or finding a still pond and putting woven bags of crushed husks in them into the water. The toxins from husks release the same chemicals that the tree’s roots emit and would stun fish, causing them to float to the surface of the water (this is now illegal). The edible parts of the plant are clearly the nuts, which can be eaten raw or cooked. Also worth noting, is beware when cracking black walnuts to wear clothes that can be stained, as the juice inside the husks/shells will stain anything it comes in contact with a dark brown, though this can also be used as a wood stain for furniture. Early American settlers would also use this juice to dye hair.
Nutritionally, one cup of chopped black walnuts contains 773 calories, consisting of 74 grams of fat, two milligrams of sodium, 12 grams of carbohydrates, and 30 grams of protein. It contains one-percent of the daily value of vitamin A, four-percent of vitamin C, eleven-percent vitamin E, four-percent vitamin K, five-percent thiamin, ten-percent riboflavin, three-percent niacin, thirty-six-percent of vitamin B6, and ten-percent of folate. Furthermore, it is noted as being low in cholesterol and sodium, a good source of copper, and a very good source of manganese. Black walnut also contains magnesium, phosphorus, iron, calcium, potassium, zinc, and selenium.
Besides being edible, the black walnut is highly prized for its wood. It has a dark brown coloring and very straight-grained heartwood. Furthermore, it is heavy, shock-resistant, and strong, yet can easily be worked and/or split. In fact, black walnuts are prized by gun manufacturers, who use them decoratively in gun embellishments, such as gun stocks. The wood is also used for furniture, paddles, coffins, flooring, and a variety of other products.
So, remember to try and eat one wild food every day! If you have any questions or comments or ideas for wild food articles or recipes, please email [email protected].