"SEQUOIA NATIONAL PARK, Calif. -- The California forest that is home to the biggest and oldest living things on earth, the giant Sequoia redwoods, also suffers a dubious distinction. It has the worst air pollution of any national park in the U.S."

"Crews are working to ensure that no more structures are damaged by a wildfire burning across more than 30 square miles of Michigan's Upper Peninsula."

"Brazil's President Dilma Rousseff on Friday vetoed divisive elements of a new law that relaxes the forest cover farmers must preserve on their land, taking a stand against the agricultural lobby that pushed a more lenient version through Congress."

"VANCOUVER - A giant 800-year-old red cedar tree has been poached from a provincial park on southern Vancouver Island, but the culprits who repeatedly returned to the site to hack it down may never be brought to justice."

"When it comes to labels assuring consumers that they’re buying green products, buyer beware. In theory such labels are intended to help shoppers make responsible choices. But many of these labeling and certification programs are overseen by the industry they are supposedly policing."

"PORTLAND, Maine -- Frank Knight's decades-long battle to save New England's tallest elm served as an inspiring tale of devotion, so it is fitting that he will be laid to rest in a coffin made from the tree he made famous. Knight, who died Monday at 103, had affectionately referred to the 217-year-old elm nicknamed Herbie as "an old friend." The massive tree succumbed to Dutch elm disease and was cut down two years ago."

"EDMONTON -- On the one year anniversary of the Slave Lake fire, here is a troubling thought. There is a good chance — an ever-increasing chance, as a matter of fact — that it will happen again. Perhaps not to Slave Lake, Alta., but to another community, or communities, nestled in the national tinderbox that is the great boreal forest stretching from British Columbia to Labrador."

"In California, May typically marks the beginning of a warm and dry summer season. This year, however, things are different. Not only has it been warm and dry for the past couple weeks; it's been warm and dry for months. So dry, in fact, that officials are warning the risk of wildfires across much of the state is going to be much worse than usual, for several months to come."

"Some of the main proposals in a draft text for negotiation at a U.N. sustainable development conference next month are being watered down at informal talks in New York, observers said on Tuesday, heightening fears the summit will fail to deliver."

"U.S. EPA is writing rules that would require pollution-discharge permits for the muddy runoff from logging roads -- regulations mandated by a court ruling that sparked bipartisan political backlash."

"The rising tide laps at the feet of local children and fishermen and submerges all but the tops of the mangrove trees of Tiwoho village in Indonesia's North Sulawesi province. At one degree of latitude north of the equator, the climate here is about the same all year round: hot, wet and perfect for the forests of salt-tolerant trees that grow along sheltered coastlines.

"The early spring of 2012 raised both temperatures and eyebrows, including President Obama's.

"ALBANY, N.Y. -- The invasive beetle that has destroyed tens of millions of ash trees over the past decade has been found east of the Hudson River for the first time, marking its closest known threat to New England, researchers in New York told The Associated Press Wednesday."

"WASHINGTON, DC -- The U.S. Forest Service is investing $40.6 million to acquire 27 pieces of land in 15 states that the agency says will help safeguard clean water, provide recreational access, preserve wildlife habitat, enhance scenic vistas and protect historic and wilderness areas."

"With spring having sprung, it will only be a matter of time before many area residents who have ash trees will find out if their trees will be added to the rapidly growing list of victims of the notorious emerald ash borer."