We all know what tree line is in Colorado: the point above which trees don’t grow. But what determines tree line: Cold? Soil conditions? Precipitation? And is tree line different in various parts of ...

LAKE TAHOE, Calif./Nev. – Liberty announced its official recognition as a Tree Line USA Utility by the Arbor Day Foundation, a distinction awarded to utilities that demonstrate excellence in tree care ...

The Arbor Day Foundation has recognized Duke Energy Florida for its tree care practices by naming the company a “Tree Line USA” utility for the 17th year in a row. The Tree Line USA Program ...

As a testament to its continued commitment to environmental stewardship and ensuring electric reliability for customers, Eversource has been named a Tree Line USA utility by the Arbor Day Foundation ...

Gnarled, dead bristlecone pine trees, which can live more than 5,000 years, stand where young limber pine grow around them. Limber pine is beginning to colonize areas of the Great Basin once dominated ...

Forbes contributors publish independent expert analyses and insights. Ann Latham writes about true clarity and its power to transform. As an avid hiker who keeps hiking higher, I was not surprised to ...