buford, a rose can have cryptic viruses in their lineage since these viruses are passed through the seed. A cryptic virus has been found in RRV infected multiflora. http://www.sipav.org/main/jpp/index.php/jpp/article/view/664/451 I think I read recently that one of the blueberry type viruses that also infects roses and is passed through the seed has been found in RRV infected roses. Perhaps either of the above is what you heard. Often virus coinfections are much "harder" on a plant's immune system than a single virus infection. Here is a link that might be useful: link to cryptic virus discussion

. Rose rosette disease is a lethal disease of rose that has been seen off and on in the Evansville area for many years. Unfortunately, 2011 appears to be an "on" year. Symptoms of rose rosette disease are highly variable, depending on the species or cultivator of rose affected. Some of the more recognizable symptoms include rapid elongation of new shoots, followed by the development of clusters of small branches (a symptom known as "witches' broom"). Leaves in the witches' broom are small, distorted and often noticeably red in color. Canes often develop excessive growth of unusually soft and pliable red or green thorns, which may stiffen later. Canes also may be noticeably thicker than the parent cane from which they emerged. Flowers may be distorted with fewer petals than normal, and flower color may be abnormal. Infected rose plants often die within one to two years. Rose rosette is thought to be caused by a virus or a virus-like pathogen. It is spread by the eriophyid mite, which is the smallest of all mites commonly found in the U.S. (less than 1/100 of an inch long) and virtually impossible to identify in the garden. The wild multiflora rose is highly susceptible to this disease and, in fact, the virus was used for years as a biological control of this invasive weed. There are no pesticides that will protect a plant from a virus disease. The miticides (insecticides for mites) registered for control of spider mites do not control the eriophyid mites that transmit rose rosette disease. While some researchers have found the insecticide carbaryl (Sevin) works against these mites, it has no effect on the more common spider mite. In fact, Sevin kills off the predators that would keep spider mites under control. Once symptoms are seen in a rose bush, it is safe to assume the entire plant is infected. Therefore, the best course of action is to immediately remove infected plants. Do not put them in the compost pile, or pile them up for later burning/destruction. Bag them and place them in the trash immediately. Destroy all multiflora roses within 100 yards of your rose garden. These wild roses can serve as a source of inoculum. Although the virus doesn't live in the soil, it can survive in any rose roots left behind. I would recommend replanting the bed with anything other than roses, at least for a few years. To prevent infection of new transplants, avoid planting cultivated roses on hilltops or downwind of known multiflora rose plantings. Space plants so that canes and leaves don't touch each other. Eriophyid mites don't have wings and must crawl from plant to plant. Proper spacing makes it more difficult for the mites to move within a planting. For more information on rose disease problems, contact the Purdue Extension Service at 812-435-5287. Larry Caplan is an extension educator-horticulture with the Purdue University Cooperative Extension Service, Vanderburgh County/Southwest Indiana. You can send email to him at LCaplan@purdue.edu.

Hello Henry: Nothing new- we get called to a lot of "problem situations" that turn out to be RRD. We saw our first RRD in garden situations some years ago- about the same time Terry did - might have been some before that misdiagnosed as weed killer damage. I've got to assume it had already showed up on wild multifloras. I used to tell people to bring their infected roses to their county extension - I don't even bother with that any more. They've probably seen enough of them. Wild multiflora roses have become significantly reduced in this area in the past few years - even the ones that were planted as highway barriers are significantly reduced. That's got to be from RRD. I assume the ones that are left are somewhat resistant to the virus. Since this virus requires a vector, that might be succumbing to natural predators as well. Here is a link that might be useful: Featured Creatures: eriophyid mite vector of Rose Rosette Disease (RRD)

Henry, I've talked with Alma and her major professor about her thesis. It's one of those written as chapters suitable for publication. Both told me that the two (of four total) that deal with RRD (then) are the two published in Weed Science with several co-authors. Can your library access Weed Science? If not, let me know. Cutting off an infected cane HAS to be done before the virus moves down into the roots (assuming stem meristem infection) and back out. I've saved several roses from different classes in my yard by catching the problem when only a single leaf node (or three on one side of the cane) were infected in fall. I saved an American Pillar in spring when it was out on a cane about ten feet from the roots. I've never saved a HT, and I've only seen RRD on HTs in spring. That may have something to do with the transmission times in fall to late fall. The one thing that (I don't think) has been addressed is what it is about RRD that ultimately kills the host rose. Epstein and Hill reported a lack of sugar to starch conversion in long infected canes. The odd thing that I watched this year was that some roses I've watched for four years finally got down to scrawney, skinny leaves often with PM and then they died in May (which was not a time of drought or too much rain- just really nice weather.) We know from Glen Viehmeyer and Percy Wright that both saw RRD overwinter in the colder parts of Canada. I don't think we know much about temperature and the whole batch of EMARviruses.