The goldspotted oak-borer, an invasive beetle responsible for killing 200,000 trees in Southern California, is now present in Ventura County. It's the northernmost reach of the insect.

The Mediterranean oak borer, a miniscule beetle no bigger than a sesame seed, has been discovered in trees around the Portland area. The invasive pest native to Europe, the Middle East and North ...

Ron Durbin, who trekked with a group into a rugged Santa Clarita canyon, quickly spotted nearby trees pockmarked with D-shaped “exit holes,” a deadly calling card. This was the work of the goldspotted ...

‘I have some weird, seemingly hollow, green, round balls falling from my oak tree. What in the world are these things?” — S.Y. You are describing an interesting growth that can occur on a variety of ...

A drive to the mountains in San Diego County means you're surrounded by nature, trees especially, which have been facing a major threat from something so small you might not even notice it. You will ...

Welcome to our tree column, “Ask your local arborist.” Each month, arborists from the Davey Tree Expert Company in Menlo Park discuss a tree-related topic from general care and planting tips to how ...