https://napavalleyregister.com/lifestyles/home-and-garden/columnists/bill-pramuk/hanging-moss-in-an-orange-tree/article_b5b3bc9a-4afd-5bc3-a433-929b46284895.html use this link for this question cause it is an articsl on this
These are known as "lichens," and they grow on tress that are declining in health. It grows in wet, sunny areas, and are rarely found on healthy trees.
