The Zoning Advisory Committee on Wednesday continued to make progress in its proposed alteration of the town’s tree-cutting bylaw, adjusting the wording in an attempt to tighten up the restrictions primarily aimed at limiting commercial ground-mounted solar developments.

After 90 minutes of discussion and tweaking of the current bylaw, ZAC chair Mary Larson-Marlowe said she didn’t feel the suggested changes were strong enough.

“My concern about these review standards is that we’re not giving the Planning Board enough to work worth,” she said. “Basically it’s all, ‘Well, we recommend this, and we’d like you to do a reasonable effort in this.’ But how can we give it more teeth?”

Looking to strengthen the bylaw, members suggested changing the percentage of the site area in residential and agricultural zones that can be cleared of trees and have the topography altered to a maximum of 20 percent, down from 40 percent. Business and industrial zones were left at 70 percent.

Larson-Marlowe noted that three recently approved solar developments in residential or agricultural zones did not reach the 40 percent mark for clearing, “but they still were massively destructive of trees.”

Principal planner John Gelcich suggested there might be a better metric to use rather than site area, referencing basal area, although he said he needed to do more research first.

The discussion was continued to Monday night, at which time the committee will attempt to finish its proposal and send it to the Planning Board for further discussion. The Planning Board has held a spot on the Town Meeting warrant for the changes to go before voters.