The "mossy spots" are lichens, which are fungi that live on the trunks of
trees, rocks, logs, etc... They dont affect the tree in any way shape or form,
and are actually an indicator of good air quality. If the dogwood is located
in full sun, that is probably causing the scortched, wilted leaves. Your
dogwood is still very young and can take a few years before it really has a
good show of flowers. Newly planted trees can also take a few years before
they really start to grow, they need time to establish a large enough root
system. Dont overlook something as simple as water requirments

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