The goldspotted oak-borer, an invasive beetle responsible for killing 200,000 trees in Southern California, is now present in ...

An invasive pest that kills oak trees continues to spread through the Willamette Valley between Portland and Salem. Oregon officials completed a two-year study this summer that found the Mediterranean ...

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 ...

Dead trees line the Salt Creek and Platte River near Mahoney State Park in June 2025. Horticulturists with the Nebraska Game and Parks Commission were stumped when they started seeing significant ...

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 ...

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 ...

‘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 ...

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 ...

Oak wilt, a lethal tree disease in which species such as Mizunara and Kashiwa oaks are attacked by insects and eventually d ...