If the japanese maple's branches are brittle and snap off when you bend them, they're dead and not coming back. You should remove them.

As for the dogwood, that sounds like a dogwood in the summer in GA growing in the sun. Is this the first time you've noticed it like this? When was it planted?

The first test for a defoliated branch on a tree or shrub is to scratch the bark with a strong thumbnail or pocket knife. If there is still "green" under the bark there is a chance (not necessarily that it will live, but a chance). The greener, the better. If the layer between the bark and the sapwood is brown, forget it.
Dogwood, jap maple, whatever, almost. There are some that will show yellow or purple beneath and still be healthy, but few. Use the "green" scratch test.
hortster

The dogwood is in shade with other tree's like pine's and oak's covering it. Last summer I remember a few of the lower limbs with yellow...leaves and didn't take it seriously ..just removed the yellow leaves. It has been planted about 12 years and hasn't really filled in with lot of branches probably due to the lack of rain and the clay soil. The Japanese lacy leaf maple limbs don't appear to be brittle. Dead leaves are falling off and it breaks my heart to see such a beautiful tree in distress. Thank you for responding. Peggy

Are the trees mulched? Have they been fertilized or has weed killer been sprayed near them? It could be antracnose. I've noticed that being more of a problem this year. Much more in fact.

Yes they are pinestrawed but probably not deep enough. No spray has been near them. The maple has been fertilized in early spring. I don't know what antracnose is. They are planted in different areas.

Anthracnose is a fungal disease that starts with the leaves and works its way in to the twigs and branches. It can be serious on dogwoods. But your symptoms really sound more like heat stress. Would you be able to take some photos of it and post them here so we can see the leaves and the rest of the tree? Especially closeups of the leaves?

Thanks for the definition of Anthracnose. Sorry I don't know how to post with photo's. If someone comes by I will ask them to do it for me. Again, I appreciate your time.

Peggy