On Saturday, May 20, the Mount Rose Preserve off Carter Road is the site for a free series of guided hikes to look for plants and animals and other creatures like this Coral hairstreak butterfly. A special children’s program on how to catch insects in sweep nets is part of the event, held from 6 a.m. to 2:30 p.m. rain or shine. Call (908) 997-0725 for more information.