With sidewalks returning to much of Circuit avenue as the Oak Bluffs streetscape project takes shape, the select board tackled one major remaining uncertainty Tuesday — the trees.

The board voted 4-0 to approve Ivory Silk Lilac trees to line the street after a recommendation from Polly Hill Arboretum executive director Tim Boland and project consultant Tim Wong. Select board member Jason Balboni was absent.

Initially, Mr. Wong said Cleveland Pear trees were considered to replace the street’s longstanding Callery Pears, an invasive species. But after feedback from the community, Mr. Wong said he and Mr. Boland began to look at alternatives, landing on the Ivory Silk Lilac tree.

The tree is native to Japan, but Mr. Boland said it comes from an American climate and is very salt-tolerant, a boon for urban trees that have to deal with salt in the air as well as on the ground.

“It isn’t known to be invasive,” he said. “It’s a plant that flowers later than the Callery Pear and it has larger flowers.”

The tree resembles a lilac bush above its five-foot trunk with large, flat green leaves, bearing large bushels of small white flowers on its branches. The lilac tree gives off a sweet smell, Mr. Boland said, attracting bees and hummingbirds. The tree is likely to bloom in early or mid-June, and boasts a bark Mr. Boland said grows more ornamental in the winter months.

“It’s a very striking tree,” he said. “Bloom time, depending on how warm it is, will last 10 days.”

Beyond its beauty, Mr. Boland said the tree is well-equipped to handle the stresses of surviving in a downtown area. Its height of up to 20 feet is especially convenient for wiring from telephone poles, he said.

“It’s often called a utili-tree because it fits under wires,” he said.

It also requires less maintenance than a Callery Pear, he said. Though, the lilac trees will still need some pruning.

“Just a tough character, so it’s a good plant for this purpose,” Mr. Boland said.

Mark Crossland, the town’s landscaper, agreed.

“I think it’s a perfect replacement for the [Callery] Pears,” he said.

Included with the new trees will be new planters on Circuit avenue, designed to be less cumbersome than the old wooden ones, and more friendly to drivers.

Mr. Wong said each space at the top of Circuit avenue past Healey Square, where parking will remain diagonal, is designed to fit a 17-foot vehicle.

“The trees will be set far enough back from the bumper,” Mr. Wong said.

The lilac trees will add a change order of about $3,000 to the $1.65 million Circuit avenue revitalization, town administrator Deborah Potter said. The added cost will contribute to a total of around $10,000 in overages on the project so far, she said. Most of the other added costs have been in service of bringing stairs up to code after changes in elevation were made to sidewalks.

A few additional change orders may be on the horizon, Ms. Potter said, but their costs will likely be minor.

“That’s pretty good then, cause they’re a long way through,” select board chair Brian Packish said.