The windblown leaves of a large black walnut tree on a rainy afternoon looked just enough like palm fronds to remind me of a Winslow Homer watercolor. However fanciful, this was not the tree’s only parallel to a coconut palm. Large walnuts pelted the ground all around me with audible thuds.

I was here to collect a small bag of these nuts, but I proceeded gingerly, with one eye fixed on the great tree’s canopy. I’d seen what these cannonballs (the size of limes) could do to a car’s hood, and didn’t plan on suffering a similar pummeling. Fortunately, the rich, water-soaked soil at the base of the tree was littered with the fragrant nuts, and I would be in the danger zone only a short time.

Though wild black walnut (Juglans nigra) is delicious, its defenses thwart all reasonable efforts to get at it. Under the thick outer hull lies a yet harder inner shell to breach, and once within that, the nut’s brainlike convolutions render it almost impossible to extract in any large quantity. One method often recommended in the past was to drive a car over them. Apparently, flat tires and bulletlike projectiles were common enough that most modern nut enthusiasts have turned to more surgical means of extraction — like large wooden mallets.

It should be noted that the walnuts sold in cans in the supermarket are English walnuts, which are not native to New York City.