Tracy K. Smith’s first poem to appear in The New Yorker, in 2009, was “Alternate Take: Levon Helm,” about the great musician and member of the Band. Smith was recently named the Poet Laureate of the United States, so the demands on her time have increased. She takes us into the woods around her home to describe the “effortless sense of clarity” she seeks in her work, and meets up with the local fauna along the way.