Learn about the fascinating life of bluebirds, their behavior, reasons for their decline, and restoration efforts. Instructor Sylvia Marek, Arboretum naturalist, created the Arboretum bluebird trail in 1988 and has monitored it for 33 years. Indoor presentation followed by a walk of the bluebird trail. Rain or shine. Fee: $20. Meet at the Visitor Center. Register by May 3. This class may be offered virtually if necessary.