Krista-----I'm reading this with interest because I think I found some on an old New Dawn plant--I'm not sure if it is RRD because I've only seen pictures.
I hope Ann responds to this!!

Florence

Can the disease be spread from canes of an infected rose that might come in contact with the canes of an uninfected rose, such as if the canes cross and scratch?
A M.S.thesis in Missouri tried to inject infected sap but that didn't work. BUT last fall, I saw one sick cane of James Galway and the cane rubbing it also get RRD but the RRD in the second was a very young infection. In the case of my JG, it was probably phloem to phloem contact that did it and with the thesis, he may have injected the sap too deep into the stems.

Or does the rose have to have the mites on it to be infected?
The Profs at Iowa State graft spread RRD but grafting buds from infected multiflora onto other multiflora without mite involvement.

I was also wondering about roses that have one infected cane, but the whole plant does not show symptoms yet.
I watched a small Nearly Wild at LMU in Harrogate TN that had one sick cane; then a year later, the same sick cane; then two years later the same sick cane and another sick cane; then three years, three sick canes and one remaining healthy, then at five years, only one sick cane left.

If a rose cane has RRD symptoms, but only that cane on the plant has symptoms, does that suggest that the mites were feeding on that cane only, or might the mites have been on the entire rose plant, but some canes were somehow "resistant" to becoming infected by the mite?
So far, I don't think there are any resistant roses. There may be canes whose roots aren't interconnected to the sick area very efficiently. I've had my hopes up for several roses being resistant, only to keep looking and listening and find that same cultivar infected elsewhere. Often the protection was that the rose wasn't actively growing in mite activity seasons.

When the rose plant first shows symptoms, is it more often only on a cane or two, or do the symptoms tend to show over many canes on the rose?
First symptoms are either at a single leaf node or at the end of a new cane whose end then goes bonkers (the multiflora on the intro page of the webbook is such an apical infection.)

As I understand it, the disease progresses as it spreads from a cane and down to the root of the plant. Once it's in the roots it can spread throught the root system to kill of the entire plant.
But it doesn't always kill the rose fast. Which is really the bad thing because a sick rose spreading disease is worse than a dead rose.

So, sadly, even if only one cane shows symptoms, then the whole plant could be doomed anyway?
It's doomed without some sort of mechanical intervention. As in, with a spready gallica, something cuts the roots and the roots no longer share sap. Or a huge host of beneficial mites,etc. come in and wipe out the vector mites.

Please send me one image to abpeck @ att.net (removing spaces).

Thanks Ann, for the info.

Another question came to mind.

Do the vector mites leave signs when they feed on the leaves, such as stippling of the leaves or webbing?

No signs from the mites. Webbing is from spider mites, which are barely visible without a land lens or loop. To see the RRD vector mites, you'd need 20x magnification. And they tend to be solitary. (The RRD vector mites are lengthwise the length of a foot on an aphid, not an aphid leg, an aphid foot.)