Others will explain this better than I can. This is what I know about the mites in simple terms. When the mites land on your rose they immediately begin crawling for the tender new growth. Where they enter the plant to feed and lay their eggs. In order for a miticide to kill the mite it must be a systemic. Then as with all insects resistance to all insecticides or miticides builds quickly. It would need to be applied in early spring and all year every year. There would need to be a rotation of chemicals. In all likelihood would not be successful as the mite needs to bite the plant first to again entry. Then it is already to late. I need to think more about this before commenting further.

I was under the impression that miticides that are generally available to purchasers will NOT work on RRD mite-carriers. There is nothing that can be sprayed--or everyone would be spraying them and we would have no RRD problems.

It is also my understanding that mites "travel" by breezes that blow them sometimes rather long distances and then drop them on a rose that they proceed to infect. However, by the time you see the symptoms, the RRD mite is probably long gone, sailing away on another breeze--leaving you to deal with the infection. In other words, we have no way of knowing when an RRD mite lands on our roses so we have no idea when we should be spraying (assuming there is a spray that works). By the time we find out the mite was there (because the rose is now sick), the mite probably already went traveling by wind to someone else's garden.

Someone correct me if I'm muddled about RRD facts--OK? : )

Kate

Here is one link there are many more. Under management They tell how the mite can be found in crevices and inside new growth.eriophyid vector of Rose Rosette Disease (RRD) of roses ...

Here is another that that includes a field test of miticides and their effect on eriophyoid mites. Eriophyoid Mites: Their Biology, Natural Enemies and Control - Google Books Result

Both of these comments are consistent with my understanding. I had read that they can only crawl like 9 ft a year and my roses with RRD are in corners with board fencing. So my thought was maybe they are living and breeding without being blown away.

The miticide idea came from the article Henry shared on the most recent research. They suggested miticide for control.

Do they overwinter? Does anyone know the lifecycle?

Thanks!

Susan

They can overwinter. The RRv vector mite was studied in great detail for a PhD at West Virginia under Dr. Jim Amrine, and Dr. Kassar with excellent qualifications couldn't find a job in academia.

Take a look at some related mites that are much easier to see, or at least to see the symptoms they cause. Blister mites is another name for them, and they cause the 'pouching out' growths on leaves of many plants at this time of the year. They (IIRC) always cause leaves to make (for lack of an acceptable better description, and because I dont' know the scientific term) skin-tick like protrusions upward on leaves. Poison Ivy and Maple Leaves are the ones I see most often, and what continues to surprise me is that not all the leaves on a stem are affected, just two to five, which means that waves of the blister mites hit, but not forever. I may be grasping for any good news, but I wonder if waves of P. fructiphillus work the same way.

Ann, Since eriophyoid mites are host plant specific then wouldn't they overwinter on the rose. So the mites that feeds on roses would over winter on roses. If thats true then Susan's roses back in a corner could produce many generations with no winds to move them on. But she would see more evidence of rrd on the bush.

Winter dormancy forces mites into a immobile stage that (according to Dr Amrine) looks like very small grains of yellow rice. Two winters ago he found the overwinter form on roses in northern WVa, where he hadn't seen them before.
One problem with dealing with such very small animals....could they be overwintering somewhere else?
Or in some other part of a rose plant...maybe the hips.

P. fructiphilus was first described from rose hips in southern eastern California.

But most fructiphilus aren't found in hips, they are on protected parts of stems.

Cold may or may not affect them; coldest reports of RRv are in Zone 3 in Canada.

Which may lead to the question....are there subspecies of fructiphilus? Naming of species/species differentiation is based on the 'plates' arrangement on the head end of an eriophyid mite....and that is best seen at 100x magnification which are fixed mounts with emersion oil and phase microscopy.

"The April 15-16, 2013 conference on rose rosette virus recommends: "Current control strategies include keeping roses in good vigor, pruning, mite control, and cultural controls such as reducing water on leaves."

H.Kuska comments:

I assume that the "good vigor" is to keep the immune system at its best. Thus, you may want to utilize known immune system boosters such as hydrogen peroxide and/or salicylic acid (home gardners normally use aspirin as a salicylic acid substitute).

"pruning" could be important in two ways. The first is that neighboring plants do not touch each other so that there is not a walking bridge available to allow infection of neighboring plants. The second is that if you prune in the spring you can be removing mite eggs.

"reducing water on leaves" may be important because the mites need water to survive. They may not be as attracted to a dry leave as to a wet one."

I was at that conference and rose immune systems weren't mentioned. And I did sit through all the talks both days.

Ann, if you put the quote into Google, you will find the following:

https://www.google.com/webhp?hl=en&authuser=0&gws_rd=ssl#newwindow=1&hl=en&authuser=0&q=+%22Current+control+strategies+include+keeping+roses+in+good+vigor%2C+pruning%2C+mite+control%2C+and+cultural+controls+such+as+reducing+water+on+leaves.%22+

I was the one equating "good vigor" with a healthy immune system. My exact statement is: "I assume that the "good vigor" is to keep the immune system at its best."

If you can suggest any other meaning as to why they included "good vigor" under current control strategies, please share that meaning with us.

Good vigor could reference the way a rose is grown...water and fertilizer.

Good vigor, IMO, is a really odd way of implying immune system maintenance. But I don't have much experience with immune system literature.