“I feel forest breathing / and hear the inexorable growth of the wood,” the sculptor Giuseppe Penone wrote in 1968, “I match my breathing to that of the green world around me.” Penone, who is now 73, has long been mesmerized by nature, especially trees, which he sees as sculpture. He describes a tree’s growth as a creative process “made up of fingerprints, finger marks, traces of oil … felt, followed, touched, point by point.” To celebrate the launch of Arbres, a book by Henri Claude Cousseau, 30 of Penone’s unpublished drawings of trees are here on display, as well as seven etchings called Transcription musicale de la structure des arbres. A poetic homage to the green world around us. —E.C.