Diane Houston at aboretum dedication

Of the dozens of different tree species in Forsyth Park, the ginkgo is Diane Houston’s favorite.

The ginkgo isn’t native, the president of the Savannah Tree Foundation concedes a little regretfully, but the tree has a showy way of dropping nearly all its yellow fan-shaped leaves en masse in late fall to create a golden carpet below it.

Last year, Houston hurried home to get her camera the December day the ginkgo let loose its leaves.

“The whole ground was covered, the park bench was covered. It was a spectacular shot,” she said.

On Tuesday, that ginkgo and the 51 other species of trees scattered around the 12 northern acres of Forsyth Park were dedicated as an arboretum. City officials have been planning the arboretum for years – many of the trees are mature and have long sported ID tags – but waited until after the restoration of the Fort and construction of the bandstand were complete to make the living museum official.

The mayor and city council members unveiled an interpretive sign that tells the common and scientific names of each of the numbered trees in the park.

Some, like the live oak and magnolia under which the sign sits, are easy to pick out. But others, like the green ash and the fringeflower, need a key for all but dedicated arborists.

The Forsyth Arboretum is unusual in several ways, said David White, who heads the city’s Park and Tree Department.

“Usually arboreta are measured in the tens to hundreds of acres,” he said. “We have 12, and it’s in an accessible downtown location. It’s part of a multi-use public park. You don’t have to pay admission to appreciate it. Anyone can come any time.”

Savannah boasts a long history of being tree friendly, said Bill Haws, administrator of Park and Tree’s forestry division.

Along with Philadelphia it was among the first of American cities to organize its tree planting efforts along streets, parks and squares. The city’s Park and Tree Commission dates to 1896, a fact evident in the maturity of the city’s street trees.

The trees average about 2 feet around their trunks in Savannah, while most cities see more like 14-inch average girth on canopy trees, Haws said.

Diversity of those trees is a newer concern. In 1987, a tree survey showed that more than half the urban forest was made up of only five species. Since then there’s been a greater emphasis on getting more species planted.

The arboreteum provides an educational component geared to that diversity.

“This is a place where you can walk around and in half an hour point out 50-some species of trees,” said Houston, whose organization already sponsors popular tree walks in the park. “It’s wonderful.”