The spine of the Appalachian Range runs north and south through the Mid- and South-Atlantic states, a rumpled stretch of mountains that long has provided a corridor for species. One uninvited species, the Hemlock Woolly Adelgid, arrived in 1951, and since then has attacked hemlock forests once commonplace in Shenandoah National Park, the Blue Ridge Parkway, and Great Smoky Mountains National Park. Since 1988 the National Park Service has been battling the tiny insect, and has met with varying success in those three parks. While much work remains to be done, there is optimism some of the hemlock stands will be saved. In the following stories, we take a look at the campaign.

An unidentified man apparently fell to his death in Zion National Park in Utah while hiking in the area of Angels Landing, officials said Friday.

The latest additions for npshistory.com and parkscanadahistory.com have now been posted to the web. Included in this update are back issues of Funding the Natural Resource Challenge: A Report to Congress; Park Newspaper: The Greenstone from Isle Royale National Park, Trends in Parks and Recreation, Natural Sounds and Night Skies Series and the Visitor Services Training Series. The March update is larger than usual with more than 200 new reports added to npshistory.com

Roads damaged as a result of California's wet winter continues to limit access to Yosemite National Park, with Highway 41 from the south closed to traffic and Big Oak Flat Road leading to the Yosemite Valley closed as well.