Children and adults can explore the relationship between plants and people at Tree Adventure, a new exhibit opening Saturday at Morris Arboretum of the University of Pennsylvania.

This permanent outdoor exhibit will offer visitors a bird's-eye view of the forest. From Out on a Limb, a 450-foot-long canopy walk that is five stories above ground level, visitors can cross a swaying suspension bridge to Bird's Nest, scamper onto Squirrel Scramble's rope netting skirting two towering trees, head to the top of the Wissahickon Vista platform, or just continue to wander the walk. With Passport to Adventure, visitors will be guided to interactive stations throughout the arboretum's 92-acre garden.

Tree Adventure's exhibits will introduce visitors to the critical role that trees play in our environment, offering the message "We need trees, and trees need us."

Tree Adventure. Opening Saturday at Morris Arboretum of the University of Pennsylvania, 100 E. Northwestern Ave. Hours: 10 a.m. to 4 p.m. weekdays, 10 a.m. to 5 p.m. weekends, open until 8:30 Thursdays through August. Admission: $14, $7 for children ages 3 to 17 and students (must have ID), $12 for seniors 65 and older, $7 for visitors who enter arboretum without a vehicle or use public transportation, free for members and children under 3. Exhibit is free with regular admission. Information: 215-247-5777 or www.morrisarboretum.org.

Crafts and fireworks

Celebrate America's birthday at the sixth annual Peddler's Village Celebration of Freedom, scheduled 4 to 10 p.m. Saturday.

The fireworks start at 9:15 p.m. and will be presented by Pyrotecnico, creator of the pyrotechnic displays for the Eagles and the Phillies. The rain-or-shine event will have children's crafts activities, entertainment, and picnic-style favorites for sale. Kids can also hang out and have fun with Giggles the Monkey of Giggleberry Fair in Peddler's Village.

6th Annual Celebration of Freedom, 4 to 10 p.m. Saturday at Peddler's Village, Route 202 and Street Road, Lahaska. Fireworks start at 9:15 p.m. Admission and parking: free. Information: 215-794-4000 or www.peddlersvillage.com.

Vegan BBQ

Families can celebrate the Fourth of July at Clark Park in West Philadelphia with a vegan-style picnic hosted by Public Eye: Artists for Animals' Kids Club and the Vegan Bus organization.

Kids can enjoy a down-home vegan barbecue meal and have fun with hula hoops, lawn games, musical instruments, and an art project. Attendees are encouraged to bring a vegan or vegetarian picnic lunch, blanket or lawn chairs, and drinks. Additional items such as veggie dogs and burgers will be provided.

The Vegan Bus is a group of activists, artists, and speakers who travel on a full-sized school bus that runs on waste vegetable oil. They will use art, performance, and other media to raise awareness of the connections between dietary choice, personal health, cultural ethics, and globally sustainable ecology. The Public Eye is a project of Mobilization for Animals (PA), a nonprofit organization.

Kids Club July 4th BBQ with the Vegan Bus, 11 a.m. to 3 p.m. Saturday at Clark Park Section B (the bowl near the playground), Chester Avenue between 43d and 45th Streets. Admission: Free. Information: 215-620-2130 or www.publiceyephilly.org.

Contact Monica Peters at mpeters@phillynews.com