I have a love-hate relationship with black walnut trees. As a child we had a swing in one of two very tall black walnut trees along the lane. We could swing out a great distance. It was like flying, I thought.
But in the fall, walnuts rained down and we girls were expected to don gloves to pick up the walnuts and spread them in the lane so car tires would squish the pulpy hulls before we got out the hammers to crack open the hard shells underneath for those tasty nut kernels. Gloves were essential when handling the hulls. Otherwise hands and tools too were covered in a dark brown color which was difficult to remove.
Despite that pulpy covering and the hard shell around the nut kernels, they are a useful food for squirrels as well as raccoons, turkeys and bears. Like many nuts, the walnut provides protein, carbohydrates and fat, necessary for storing energy for those animals that hibernate.
Walnuts produce varied-size crops. Some years there are so many, we can fill buckets and buckets of walnuts to process, leaving some for wildlife, of course. Other times, like this year, the walnut crop is pretty sparse.
I’ve never had a walnut fall directly on me, but I did one time drive a rented car through a large grove of black walnut trees in a windstorm. It rained walnuts on the car. I was so sure the car rental company would find dents for which I’d be responsible, but hard as those walnuts fell, they were not able, thankfully, to leave dents on the car.
Walnut hulls and leaves have an easily recognized odor. I find it interesting, but nose-tingling; I wouldn’t recommend walnut hull perfumed bed sheets! This odor is from the polyphenol exuded by the tree. As you may know, when this polyphenol leaches from the tree, it controls what will or will not grow in the vicinity of the tree. If you are planning to plant shrubs or flowers near a walnut tree, do your research to find out which ones are not affected by this polyphenol.
That odor helps me to identify walnut seedlings when squirrels graciously plant walnuts in my gardens. If I find the seedlings the first summer, they are easy to pull out. If the seedlings hide until a later summer, their deep roots make it very difficult to remove them entirely.
At this time of year you’ve probably noticed some walnut trees are festooned with webby silk bags. The bags are the homes for fall webworm larvae. Fall webworms use a variety of trees; I’ve seen their bags in hickory and cherry trees, but in this area they seem to prefer black walnut trees. These are different from the tent caterpillar nests one sees in the spring. The fall webworm larvae eat the leaves encased in the silk bags, so some trees become partially naked before the leaves would normally drop. Do these larvae hurt the trees? No. Mature trees have stored up enough energy for them to continue living in good health. I have never seen fall webworms in the branches of very young trees, which might indeed cause a set back in growth.
Black walnut trees are sometimes planted as “money in the bank.” Maybe the person who planted them won’t benefit, but the next generation might sell walnut trees for lumber. The wood is used for furniture, as well as flooring, veneer, and gunstocks.
Black walnut trees are indeed interesting. I hope you enjoy looking for black walnut trees. They may be intentionally planted or growing informally in a hedgerow or an untended field.