The Winthrop Planning Commission will lead the town’s celebration of Arbor Day on May 30 at 5 p.m. in Mack Lloyd Park. The celebration is aimed at caring for the trees that shade the park, focused on preparing the trees for a new season of growth. Participants are encouraged to bring a pair of gloves and pruning shears, saws or loppers. For more information, contact Town Hall at 996-2320.