Not all invasive species are trouble. When the land is stripped of life and turned into dust, cheatgrass and sagebrush, the swallowtails seek out alfalfa that has escaped from nearby farms.

Western Tiger Swallowtail, Papilio rutulus

Lilacs will also do. It’s not that these are their natural haunts, but they are a darned site better than letting the rich tapestry of the land go wild. And make sure to leave a mock orange for the caterpillars. The swallow tail is your average mock orange taking wing. Look below.

Notice the herd of cows and their calves trying to evolve into butterflies to get out of that wasteland of inedible sticks? That’s the way.