Visit the Art Gallery of the Guild of Harwich Artists on Saturday, July 14 for a free demonstration of how to paint trees with watercolor on yupo paper, a plastic medium that allows the paint to slide on the surface and produce sometimes surprising results!  Anne Briggs will lead the demonstration from 2 to 4 PM at the gallery located at 551 Main St. (Rte. 28) in Harwich Port (508-432-7622  www.guildofharwichartists.org) with free parking across the street at the Tourist Information Center.