“I began my writing career by exploring the tracks humans have left in nature. Now I’m mostly interested in the tracks nature leaves in us.” That’s author Gary Ferguson. He says that nature provides beauty, mystery and community, traits that each of us very much needs. He is the author of 25 books. We talked with Gary Ferguson a few months ago about his latest “Land on Fire.” Today we’ll talk with him about “The Carry Home” a haunting meditation on wilderness, conservation, and grief, written following the death of his wife in a canoeing accident.