Is this scurfy rose scale?
I have this on a Zephirine Drouhin rose in my courtyard, and the infestation seems severe. This rose isn't particularly strong, as for years it was in the shade of a shed, where I had planted it in the hope it would quickly reach up over the shed to where the sun was. I finally removed the shed completely a year ago, and the rose suddenly looked very well, putting on healthy growth and flowering. I am very reluctant to take it out because it is deeply planted in a rather awkward space which was created for it when I had my patio re-laid, and while I could probably get the old rose out, putting in a new one is going to be a problem, as I would have to wait a couple of years to avoid replant disease, and I don't really have the space there to do what I have done before which is plant a new rose into a cardboard box. Any ideas? I have the winter to treat it, but would rather not cut it back hard if I can avoid it, as the whole point of this rose is for it to climb up to the top of my 6' wall! However will do that if it will recover and be healthy and flowering. Thanks for any advice you can offer.