That looks like lichen to me. It's natural and won't hurt your tree.
Douglas is correct. You find it very common on many varieties of Crape Myrtles.
That's a relief. Thanks y'all!
Often lichen grows on trees that are stressed or do not get enough sun exposure. Think if there is a way it could be happier, such as enough water, is soil eroding away and roots exposed, mulch coverage... Like the others said, lichen will not hurt it. However, if it gets real thick and cakes on, that dictates the plant is stressed.
My poor tree is stressed. I dug it up in the middle of summer last year and moved it to a new location. I am pleased that it is still living, all things considered.
Maybe you can apply a basic tree and shrub fertilixer like 10-10-10. Did you amend the soil well and give it a root stimulator like Upstart or B1 when you transplanted it?
did you ever find out what this is on the trunk and branches? Think I have one of mine thats starting to look like this! The 10 others are fine.
Micky, we identified it as lichen, common to many varieties of crepe myrtle.
Micky D ( Love the bike!) We have lichen on many of our trees here in Oregon. Just so moist! Like Douglas said, its not going to harm your trees.
I am fairly sure that Lichen is what Hummingbirds use to line the outside of their nests. So, it will not hurt any trees or shrubs.
Looks like lichen. Show your photos to a nursery center.
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