WASHINGTON STATE — Sherwood State Forest in Washington’s Mason County escaped the industrial clear-cutting that transformed much of the Northwest last century. …Last year, those islands of protected forest shrank even further as Washington’s Department of Natural Resources auctioned off rights to log almost 160 acres of Sherwood Forest, located about 40 miles southwest of Seattle. …This story is hardly unique. Throughout Western Washington, pockets of state forestlands that were logged in the early 1900s have regrown into ecosystems that sequester tons of carbon and serve as valuable wildlife habitat. …These regrown forests also represent a potential bonanza for timber companies, however, and they don’t benefit from protections given to most old growth on state lands. …A paper published last year by the independent research nonprofit Resources for the Future found mature forests sequester more carbon than younger trees do.