Elysian Park is L.A.'s very first park, and since its creation in 1886, has seen a constant battle between those who want to develop it and those who want it preserved. Yet one secret spot survives -- Chavez Ravine Arboretum, which Angelinos drive right past on their way to a Dodgers game or the Los Angeles Police Academy.

Southern California's oldest arboretum, Chavez Ravine fills a narrow canyon planted with more than 100 varieties of mature trees, some of which are more than 100 years old. There's a fruiting guava, a cork oak with its spongy bark, a floss silk tree with its weird, thorny trunk. All around are woodpeckers, hummingbirds and ravens. Weekdays, the place is serene and peaceful -- just birds and folks who love trees.

Looking high into a cigar box tree, Donald Hodel, the author of "Exceptional Trees of Los Angeles" and an environmental horticulture adviser for the UC Cooperative Extension, identifies it by its Latin name -- Cedrella toona.

"This is probably the biggest specimen I know of in California," he says.

Hodel comes here a few times a year to inspect the trees: natives of Asia, Africa, Australia and South America. One of his favorites is the elegant Tipu, from Argentina, whose soaring trunks unfurl into clouds of yellow blossoms.

"Look at the spread of the canopy," Hodel marvels, stopping to take a picture. "I mean, that looks like a 125-foot spread on this thing. Beautiful!"

First planted in 1893, Chavez Ravine Arboretum is maintained by L.A.'s Department of Recreation and Parks. It's one of few such places open to the public, unguarded by fences or fees. On weekends it fills with kids and families.

Inspecting the knotty trunk of an ancient Umbu tree, Hodel points out the damage done by dumping hot charcoal and climbing on it.

"It takes a beating," he says. It's not the only damage -- others are carved up with initials, and all the trees are in desperate need of pruning.

Yet L.A. city budgets are tight, and locals have had to pitch in to help preserve the grove.

Christine Peters, president of the Citizen Committee to Save Elysian Park, says her organization organizes quarterly get-togethers to mulch and deep-water the trees.

"The city just doesn't have the manpower to do it," she says. "They don't have the money or the infrastructure to provide this kind of care."

It's a place worth preserving. Admiring one of the oldest and largest Cape Chestnuts in North America, Donald Hodel calls it a "spectacular" tree.

"These clusters of flowers are beautiful," he says. "And it will probably bloom for about three or four weeks."

He's in no hurry to leave, and, like the birds, seems perfectly at ease among these giants, hiding here in plain sight. Meanwhile, up on the boulevard, another wave of cars zooms past.