Chemical maker turns to trees to clean air

Dow Chemical Co., the nation’s largest chemical maker, may employ a new weapon in the war against smog: trees.

For years scientists have known that trees work as a crucial natural filter, but no company or municipality has used reforestation as a strategy to remove the widespread pollutant from the air.

Now, Dow is looking at planting new forests of water hickory, Texas red oak and cedar elm, among other native species, to help control additional pollution from a $4 billion expansion of its massive manufacturing complex in Freeport, about 60 miles south of Houston.

Read more about the plan, and why Texas regulators have doubts, at