The Hopkinton Trails Club will host its next monthly walk on Sunday, May 17, at 1 p.m. The Upton State Forest heron walk will feature easy walking trails from Lake Whitehall to a heron rookery. Participants will meet on Pond Street where it crosses the south end of Lake Whitehall, between School Street and Christian Way. For more information, visit hopkintontrailsclub.com.