I have this one little bit of fall purple left.
I had similar ones of unknown source, but a strange thing happened: sorts of "flowers" showed, the big leaves fell and it developped a kind of "cancer" of some sort, more and more flowers that swelled and then gradually turned brownish. A bit like those that
Wires_Guy_wires posted, but it seems that the disease on mine was ten times worse.
And they had a very strong (though not unpleasant) smell.
Surely a sign of a fungal disease, so I totally removed the plants.
The Dutch already sent us the "Dutch Elm disease", I don't want them to send us more UBD (unidentified bonsai diseases). Let's make our country immune again! Let's build walls and borders, hire more mercenaries to track down the germs and kill them before they enter our "Douce France"!
Sorry for "the Germs", I didn't mean no harm, you know I even have Virus friends. Some of them are so well-behaved that they have a special place in my biotope.
Back to the sick maples:
I first thought of binning them at the local selective dumping site, but if they're diseased, I think I'd better let them dry out, then burn them.
Best option, innit?