The list of diseases attacking trees in the Pacific Northwest grows every year. A pathogen new to Pierce County brings an added concern: It can injure people. A research project using citizen ...

Q: I have a beautiful green ash tree in my front yard and hope to keep it protected from the ash borer as long as possible, but today I noticed a lot of leaves have fallen off. There are little dark ...

A group of young cedar trees infected with blight - N. Mitchell/Shutterstock There's nothing quite as majestic and imposing as a fully-grown cedar tree with its broad horizontal branches and fragrant ...

The list of diseases attacking trees in the Pacific Northwest grows every year. A pathogen new to Western Washington brings an added concern: It can injure people. A research project using citizen ...

A new tree disease has spread in forests in Massachusetts, joining invasive pests and climate change as top priorities for foresters to address. The state has found beech leaf disease in more than 90 ...

Lichens survive in a very wide range of habitats worldwide. Amazingly, more than 400 species can be found in Maryland.

Q: I recently noticed a black, tar-like patch on my tree trunk, though it’s not tacky like actual tar. Are these insect eggs? Dried sap? Do I try to scrape it off? The tree has lichen but I don’t ...

The list of diseases attacking trees in the Pacific Northwest grows every year. A pathogen now found in Bellingham brings an added concern: It can injure people. A research project using citizen ...

Waiting until the leaves drop in fall is a rule of thumb for pruning shade trees, mainly because you can see bare limbs better, and the job is less “messy” without leaves attached to the cut branches.

If you spot tiny holes and piles of sawdust on your tree, bark beetles could be the culprit. Unfortunately, the solution ...