This is a preview. Log in through your library . Abstract Four types of pattern in the structure of ponderosa pine forests of central Oregon can be recognized: (1) differences in relative density, ...

In a universe of unexplained phenomena, add this: a tree that leans toward the equator no matter where it grows. The Cook pine tilts northward in the southern hemisphere and southward in the northern ...

A critical species to the ecosystem is facing a variety of threats. This Earth Day, ABC News is taking a look at solutions for issues related to climate change and the environment with the series, ...