March 24 is Palm Sunday, which means that millions of Christians across the country will be celebrating Jesus’ entrance into Jerusalem by carrying palm leaves, often shaped in the form of a cross, into their places of worship. Where do these palms come from? Most likely they have been imported from one of a few Latin American countries: Guatemala, Belize, or southern Mexico, for instance. And most likely, they have been harvested in a manner that is harmful to the environment. Harvesters are often paid by volume rather than quality, and they have a strong incentive to cut as many...