Answer: That orange growth is lichen, not a rust pathogen. Lichen do not harm the tree or shrub in any way. They tend to grow only on that outer bark and stay there, not growing deeper into live ...

I’ve seen a fungus-like growth on several trees in the neighborhood. It’s a pale gray-green color with a frilly texture, and it coats much of the bark on some trunks. Can we do something about this ...

Lichen grow harmlessly on tree trunks and no control is needed. In fact, presence of lichens on healthy trees should be welcomed as likely positive indicators of lower levels of air pollution and a ...

This photo shows a lichen growing on hickory tree bark. Folks sometimes become concerned when they notice strange gray-green patches on the trunk or branches of a tree. Should the growths be removed?

Once upon a time, my street used to be loaded with towering, shade-providing tall trees. It was a gorgeous tree-lined street, similar to the reputable Tree City USA award-winning streets throughout ...

Over the course of many years working with trees, hundreds of people have asked me about “that stuff” growing on the bark, or hanging from the branches of trees. What is it? Is it a disease? Is it ...

My tree has lost all its leaves and the bark now has some fungi growing on it? Is lichen killing my tree? Lichen (pronounced lie-ken) gets a bad rap based on its appearance alone. It has been on our ...

Q: I am worried about the grayish-green, flaky, roundish spots I am seeing on big tree trunks and branches this spring. I can scratch it off with my fingernails. I think that it is killing my trees.

A couple of people have recently asked if the grey moss-like growth on the limbs and twigs of their trees and shrubs is the primary source of their decline. Trees and shrubs often have this sporadic ...

The seasons are changing from fall to winter, and one of the major changes to the environment is that the deciduous trees have lost their leaves. Evergreen trees may still have green needles, but all ...