FREEPORT, Texas (AP) — Before Houston and its suburbs were built, a dense forest naturally purified the air along a stretch of the Texas Gulf Coast.

It was the kind of pristine woodland that was mostly wiped out by settlers. Now one of the nation's largest chemical companies and one of its oldest conservation groups have forged an unlikely partnership that seeks to recreate some of that forest and use it to curb pollution.

The plan from Dow Chemical and the Nature Conservancy calls for growing thick groves of trees to capture pollutants downwind from a chemical plant.

The proposal faces a long wait. But it envisions a day when expensive pollution-scrubbing machines might be at least partially replaced by native trees such as pecan, ash, live oak and hackberry.