Pam wrote in message

snips
it may very well be verticillium, a soil-borne fungus that is nearly
impossible to detect until it manifests itself by killing your plant.
Viburnums are quite susceptible to this problem.

It may be possible to diagnose for yourself. Verticillium will often leave
telltale evidence as a darkened center of the stem wood or
discoloration/streaking just under the surface layer of bark. Prune out a
good size branch that has been affected, one as close to the base/trunk of
the plant as you can manage. The bad news is that there is nothing you can do for either your plant or to remove the disease pathogen from the soil. You just need to replace with something that is resistant to this problem. Do a google search under
"verticillium wilt" - not only will you get some very good explanations
and diagnostic tips on this disease, but you will also get listings of
plants that are both susceptible and resistant to the problem.
Good luck.

pam - gardengal

Pam,
I did the search and think you are correct. I also think it's
affecting a Norway Maple in my front yard. I'll cut some branches
tomorrow to look for the striping. The Virginia Extension service has
pictures of the striping and discoloration so I know what to look for.

Many thanks for your help.
Cindy Donnell