Great American Cleanup /tags/great-american-cleanup Great American Cleanup en-US SA¹ú¼Ê´«Ä± Wed, 27 Mar 2013 12:00:55 GMT Volunteers Pull 57,154 Pounds Of Litter From Natural Areas /science/2013-03-27/volunteers-pull-57-154-pounds-of-litter-from-natural-areas On a recent Sunday morning, a group of hikers paused on a heavily canopied trail to observe a bird perched high atop a tree, its body silhouetted against… Wed, 27 Mar 2013 12:00:55 GMT /science/2013-03-27/volunteers-pull-57-154-pounds-of-litter-from-natural-areas