The foliage on our arborvitae is turning brown. It is fall in Maine. Is this a natural progression, or is the tree dying?
With just that little bit of information, I can't really say if it is just natural seasonal leaf loss or some kind of a problem. You should contact your local UMaine Cooperative Extension https://extension.umaine.edu/gardening/ask/ and give them more information - how old is plant, is it located in sun/shade, how have you been caring for it, when did you first notice this problem, is it on the inside of the plant or on the outside, etc plus send them pictures. They would likely know if the arborvitaes in your area are shedding leaves now or not.