Is this Verticillium wilt?
I saw this disease mentioned on a thread about Cotinus, and now I'm concerned that it may be the answer to a question I've had for a couple of weeks - about three or more different kinds of woody plants in my garden
A pair of Cotinus 'Royal Purple' was looking spectacular one day, and the next day almost all the leaves on ONE of them had turned brown and shriveled up. A week later, one of a pair of crape myrtles (Lagerstroemia) that had been in glorious red foliage suddenly turned tan and shriveled - these were 2 different varieties, whose names escape me at the moment. Next to go was one (of 5) Stewartia pseudocamellias. Their fall foliage isn't too spectacular anyway, at least when fairly young, like mine are, but this was a seemingly overnight, total browning.
We had a VERY wet season; rain through all of June and several long wet periods with little heat through the summer. I've never had such awful foliage on tree peonies, most of which turned a uniform dark brown - even my trusty Viburnum rhytidophyllum (leatherleaf vib) had some sort of weird foliage problems (gray mottling) for the first time in about 20 years.
I'd like to see if I can diagnose this so it can be contained, If it's v. wilt, I've read that there is no treatment; so presumably the best action would be removing the effected plants.
Can I check for the cambium stain myself, or should this be done by a lab, or maybe by the Cooperative extension service?
Thanks for any advice - DtD