Friends member Diane Alden points to a specimen of the mushroom Ganoderma tsugae, thoughtfully left on an Aqueduct gatepost by a previous, anonymous walker. This was on the Friends' first guided walk from Ossining's Gerlach Park to the New Croton Dam and back, on June 18, led by Charlotte Fahn. Diane joined the group for a fascinating segment during which she identified and told about several kinds of mushrooms on the trail that otherwise would likely have gone completely unnoticed. (Photo by C. Fahn)