Anna M. Tinsley

FORT WORTH, Texas -- There's a new tumbleweed in town.

The old-fashioned tumbleweeds that long exemplified empty, desolate places have been replaced by a new symbol of blight: urban tumbleweeds -- lightweight plastic bags that get snagged in trees and bushes, pile up in streets, clog drainage systems and endanger wildlife.

A growing number of world leaders consider the bags an environmental hazard and are taking action to eliminate them.