There’s a tree killer on the loose in Oregon, and nobody knows how to stop it. An invasive green beetle called the emerald ash borer arrived in the Midwest from Asia, and it’s killed over 100 million ...

A decade ago, when the emerald ash borer first was discovered in the U.S., a confirmed outbreak was considered a death sentence for every ash tree for miles around. The insect that came to the U.S.

An invasive, tree-killing pest has made its way to Portland, spelling trouble for the many ash trees that cool residential neighborhoods on hot summer days. On Wednesday, Oregon forestry officials ...

Grass and vegetation against the trunk of a stone fruit tree provides a humid and secluded place for female borer moths to lay their eggs. Grass against a trunk also increases the likelihood of string ...

Dendrochronologists extract a small, pencil-shaped sample of wood from a tree with a tool called an increment borer. The tiny hole left in the tree's trunk quickly heals as the tree continues to grow.