They thump onto lawns, roll across sidewalks and pile up beneath trees every autumn. For some New Glarus residents, black walnuts are something to rake away. For others, they are a free seasonal ingredient worth the work of gathering, cleaning and cracking.

October is a good time to look for them. According to University of Wisconsin-Madison Extension, black walnuts ripen in September and October, particularly in southern Wisconsin. Mature nuts usually fall naturally, surrounded by round, greenish-yellow husks that gradually darken.

The native eastern black walnut is different from the milder English walnut commonly sold in grocery stores. Its edible kernel has a distinctive, rich, earthy flavor that works especially well in brownies, cookies, cakes, banana bread, ice cream and other desserts. Chopped black walnuts can also be toasted for salads, sprinkled over oatmeal or added sparingly to savory dishes.

Finding a productive tree is only the beginning. A black walnut’s outer husk stains hands and clothing, its shell is exceptionally hard, and the kernels must be dried and stored correctly. Harvesters should also know the rules before taking nuts from land they do not own.