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Fall 2011

Urban Jungle

The changing natural world at our doorsteps | Illustration and text by Patterson Clark      

October 4, 2011

Black walnuts: Worth the trouble

Black walnuts, Juglans nigra

Fortunate is the alley pelted in early October with the fat fruits of native black walnut trees. Tires from passing vehicles can crush the gooey green husks, leaving behind the rock-hard nuts for harvest.

Black walnuts are encased in a thick, woody hull, a challenge to remove but well worth the effort. Nutmeats yield an oily, woodsy flavor, much stronger and richer than that of ordinary English walnuts.

Tips for walnut harvesters

If car tires haven't husked the nut for you, follow these steps:

Wear gloves to avoid staining hands with husk pigments.

Select fruits with soft green husks. Avoid gathering fruits with black husks, as heat from the decaying husk will discolor the nutmeat and ruin its flavor.

Wearing rubber boots, stomp off the green husk to expose the nut.

Thoroughly wash nuts in water. Pour the waste water down the drain. Husks contain juglone, toxic to worms and many plants.

Nuts that float or have hairline fractures may not be good, so set them aside to use as a last resort.

Air-dry the washed nuts indoors on a screen for several days before storing in a cool spot for three to six weeks. Nuts that rattle slightly when shaken are cured and ready to crack.

Slowly crack a cured nut between the jaws of a vise. Or wrap a cured nut tightly in a tough rag, place on a butcher block or concrete floor and whack with a heavy hammer.

The hull will shatter into several sharp pieces, from which chunks of nutmeat can be picked.

Nutmeats can be frozen for up to two years or kept fresh in an airtight container in the fridge for nine months.

Sources: Center for Agroforestry, University of Missouri; University of Minnesota Extension; U.S. Forest Service; tomclothier.hort.net