After the lights wink off and the needles dry out, a tree’s job isn’t necessarily over. It turns out the same attributes that make Christmas trees so festive and pretty—the densely packed branches, the elegant shape, the magic to attract large groups of people—give them other powers, too. After they’re done displaying ornaments and standing guard over piles of presents, some of these holiday heroes go on to stabilize sand dunes, protect vulnerable marshlands from invasive species, and shelter baby fish.

Rather than send them to the wood chipper, some people are using Christmas trees to create artificial reefs, sand berms, even habitat for rabbits. The trees, it turns out, are ecological gifts in themselves.