ENVIRONMENT / Notes about your surroundings

Trunk Show--The Tree Society of Orange County is seeking items to auction off at its “Tree Music at Sunset” fund-raiser Sept. 27. The event, scheduled from 5 to 8 p.m. at the Fullerton Arboretum, features live music, line dancing and food. Past donations have included gift certificates, plants, tickets and special foods. Proceeds go to the society’s grants program for planting trees. To make a contribution, call Genni Cross at (714) 557-2575 before Sept. 14.

Bat Chance--Take a night hike Saturday to learn about the bats that make their home at the Rancho Mission Viejo Ecological Reserve near San Juan Capistrano. Stephanie Remington, a graduate biology student at Cal Poly Pomona, will lead a tour, explaining about Orange County bats, their habitat and natural history. Registration is required and is limited to adults and children 12 and older. Hours are 7:15 to 9:15 p.m. $6. Registration: (949) 489-9778.

Water Works--Recent donations from two local water treatment facilities will help the Doheny State Beach Interpretive Program expand to include education about waste-water treatment facilities, street runoff pollution and protection of the ocean. South East Regional Reclamation Authority and the Aliso Water Management Agency each contributed $1,000. Doheny State Beach provides educational programs to more than 10,000 schoolchildren who visit each year. Information: Edie Carhart, (949) 496-2704.

Bottoms Up--The dredging of Upper Newport Bay will be discussed Saturday night at a campfire in the amphitheater on Shellmaker Island at 7:30 p.m. Bring a blanket; marshmallows and roasting sticks provided. Shellmaker Island is off Backbay Drive in Newport Beach. Information: (949) 640-6746.

Send information for the Environment column to Vicky Clepper, The Times Orange County, 1375 Sunflower Ave., Costa Mesa, CA 92626. Fax: (714) 966-7711.