HOLDEN, Maine — Join David Spahr, “The Mushroom Maineiac,” for a journey through the world of fungi, 9 a.m.-noon Saturday, Sept. 6, at the Fields Pond Audubon Center, 216 Fields Pond Road. Time will be spent both indoors and outdoors learning about mushroom identification, folklore, collecting and cooking. David’s book “Edible and Medician Mushrooms of New England and Eastern Canada” will be available for purchase. Cost for the event is $17 for members and $22 for nonmembers. Call 989-2591 to register.