The oldest tree in the cathedral-like heart of Saddler's Woods - a regal, 400-year-old white oak - soars toward heaven.

I gaze upon its majesty with Janet Goehner-Jacobs, the executive director of the Saddler's Woods Conservation Association (SWCA).

The head of an all-volunteer army that nurtures the tree and 25 surrounding acres of Haddon Township, Goehner-Jacobs politely interrupts my meditations.

"Can I ask you to move your foot?" she asks. "You're standing on her baby."

Oops.

Thank God the white oak seedling in question remains perfectly perky after I raise my Nike. And bless Goehner-Jacobs for not summarily banishing me from this unexpected patch of paradise along MacArthur Boulevard.

To make sure paradise isn't lost, Goehner-Jacobs, her husband, David, and six more core volunteers - including Donna Moffett and Robyn Jeney - together spend about 3,100 hours a year working on behalf of SWCA.

Bit by incremental bit, their labor of love is paying off. The woods are not only protected from development, but are slowly being restored to a more natural condition. And while some locals still believe townhouses should have been built there, as a recent letter in a local weekly insisted, public support for SWCA seems strong.

Every year, about 100 volunteers bolster the work of the core group by helping raise money, remove invasive weeds, reintroduce native plants, and collect trash, including (so far) 300 tons of concrete. I like to help out during the spring and fall cleanups; grassroots stewardship of a precious public space like Saddler's Woods is, to say the least, a big job.

"We are the eyes and ears of the Woods," Goehner-Jacobs tells about 30 people at the Welcome Area for a cleanup last Saturday. Volunteers from corporate sponsors (Subaru, REI), along with public officials (including Peter Kroll of the Township Environmental Commission) and longtime supporters like Charlie Sedor grab gloves and tools.

A junior at Cherokee High School, where he recently performed in Les Miserables, Sedor has been an SWCA member for four years.

"Today we're doing the dirty work," says the 17-year-old Marlton resident, one of a crew of five working just downstream from where Newton Creek emerges from the ground.

"We're [taking] concrete and debris out," Sedor says, pausing with his wheelbarrow. "You never know what you're going to find. It's a never-ending battle."

Likewise SWCA's effort to clear invasive species like garlic mustard. These and several other domineering guests like Japanese honeysuckle infest the "meadow" - the nickname for the portion of the woods disrupted decades ago by construction of the Westmont Shopping Center.

Jesse Buerk of Haddon Township, a transportation planner at the Delaware Valley Regional Planning Commission, is leading the anti-garlic mustard patrol.

Buerk credits SWCA's success to hard work - and to "people who are really dedicated, have a great vision, and have a passion."

These feelings can spread. Saddler's Woods pleasantly surprised REI employee Randi Maizi of Voorhees. "I didn't know it was here," she said.

Goehner-Jacobs, who may well know the Woods better than anyone else, continues our private tour.

"To our right, there's a 250-year-old tulip poplar," she says. "And there's an American beech. It's about 300 years old."

The tree is not just beautiful but unusual; there's a cavelike opening in its trunk that you can see clear through.

It looks enchanted, like a doorway to someplace special.

Kevin Riordan purchased a one-year SWCA membership for $10 in 2008 when he was not working as a journalist.

Contact Kevin Riordan at 856-779-3845 or kriordan@phillynews.com.