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)

The following was stated by michaelg: "Our resident expert Ann says that plants are usually not cured by removing a cane at the base. If you catch it early when only one cane shows symptoms, she recommends splitting an own-root plant's crown and throwing away half the root system along with half of the top growth." H.Kuska comment: can you please supply a link for that statement so that it can be put into context? Does the above recommendation apply to all roses at all times in the growing season, or to only one (or a few types of roses such as climbers but not other types such as hybred teas, does it apply only to own root roses but not grafted roses, etc? An example of an actual quote that she has made recently: "Posted by anntn6b z6b TN (My Page) on Thu, Oct 11, 12 at 23:11 Henry, ................................... 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." http://forums2.gardenweb.com/forums/load/roses/msg101551485093.html?19 ---------------------------------------- The next 2 are posts that you recently made concerning cutting off canes in one thread ( http://forums2.gardenweb.com/forums/load/roses/msg0920343630587.html ) : "Posted by michaelg z6B NC Mts (My Page) on Mon, Sep 3, 12 at 9:45 A cluster of shoots and with crumpled leaves ( different from equally young growth on the same variety), these are additional RRD symptoms. If you remove such suspicious growth with pruners, be sure to sterilize them and bag the trimmings. Also you should take the underlying cane down to grade immediately." --------------------------------------- "Posted by michaelg z6B NC Mts (My Page) on Mon, Sep 3, 12 at 12:40 KR, What I do if I have strong suspicion but am not fully convinced is to cut the plant down, removing most of the cane and all foliage, and see what grows back. I just dug a plant yesterday that came back funny. Another one that I cut back at the same time looks fine. The latter previously had probable RRD growth high on only one cane." --------------------------------------------- --------------------------------------------- Ann's E-book is in a format that is difficult to search (I recommend a PDF format.). http://www.rosegeek.com/id5.htm In Chapter 2 she states: "A single symptom does not make a confirmation of RRD. When the growth character of a cultivar is known, appearance of multiple RRD symptoms will alert the rose owner to possible danger. Some symptoms of RRD resemble herbicide damage; a thorough search of the area around the roses for signs of herbicide use must allow for long distance herbicide drift - especially in warm weather. A rose bush outgrows herbicide damage, RRD infections persist from year to year until the death. Roses likewise outgrow �blind shoots� but the blind shoot looking growth on a rose in Georgia became more symptomatic of RRD two months later (Fig. 6). Weather damage in spring or fall can also cause contorted new growth, but comparison with growth on other roses in the same garden can be used evaluate the problem. If the damage was weather caused, the rose will out grow it. Because ot the chance of false diagnosis, each rosarian needs to think about the problem and decide in advance a course of action. Then when RRD enters a garden, the hard decisions have already been made. If RRD has not been reported nearby, and there are symptoms that suggest it, you may choose to reduce the mite population that transmits the infection. Digging up and isolating the questionable rose should also be considered. In addition, I would (and have had to) spray the bush in question and the surrounding roses at ten day intervals with Cygon 2E (following label precautions) while waiting for confirmation of RRD. Cygon 2E is the only spray that will kill the eriophyte mites. They are different from spider mites. Most chemicals approved for treatment of spider mites are not effective for the mites that transmit RRD. At present (2007) Cygon 2E is not readily available. There have been no tests to see if other miticides kill P. fructiphilus. Avid is approved for general use against eriophyid mites, but its efficacy in fighting RRD vectors is unknown." H.Kuska comment: I interpret the above to suggest: "Digging up and isolating the questionable rose should also be considered." But that nothing was said about cane cutting. ---------------------------------- In Chapter 4 the following appears: "When I find a RRD infected plant in our rose garden, it�s rogued out and burned fast. Surrounding roses are examined and sprayed. Canes of nearby roses that a mite could have fallen onto from the infected area (canes under the infection) are also removed. (To do this hurts because I hate to remove a healthy cane, but it's a logical sacrifice)." AND " Leaving a RRD-infected rose in the middle of an otherwise healthy garden is the worst course of action. Spraying the infected plant and surrounding area then rogueing out the bush is still the best course of action, perhaps with the addition of pre-emptive spraying during hot dry spells, especially in late summer, the optimum breeding season for the mites that transmit the virus." -------------------------------------- Also in Chapter 4: Our RRD infections so far: (H.Kuska comment, I will only list the "bushes that relate to cutting off the cane") "'Charles Austin'- we saved the bush by cutting the cane off rapidly fall 2001" "'Rouletti' we hope we have saved this by removing the sick cane early fall 2002" "'Fuschia Meidiland' we cut off the cane, disease came back, it's gone spring 2003" "''Gloire de Dijon' own root, first symptoms near root, one cut back didn't work spring 2005" "'Peter Beales version of Parks Yellow Tea Scented China' spring 2005 first sick out on one long cane, we cut it back, RRD came back fall 2005, we took out half the bush supporting that cane and lost the whole plant fall 2006" "'Golden Salmon Superior' Great ownroot Polyantha; tried removing the sick cane fall 2005 removed spring 2006" "'Seven Sisters' one cane sick, removed it; two canes sick three months later , spring 2006 it's gone" "'American Pillar' one sick cane cut off, so far rest of bush is healthy spring 2006" -------------------------------- Also in Chapter 4: "Case 2 - ONE STRIKE AND YOU'RE OUT Dr. Kent Campbell lives near Bowling Green, Kentucky and has been living with Rose Rosette for a number of years. There are fences near him with wild multiflora and the multiflora is sick with RRD. He can't control the fences on other folks' property, but he can control the effects of the resulting RRD on his roses. He told me about his "One Strike and You're Out" rule. When he sees aberrant growth that he associates with rose rosette on a cane, he cuts that cane back to the bud union. That's strike one. Then he watches the plant. If the plant shows additional aberrant growth, it's out. He estimates that half of his infected roses recover with no additional signs of infection. He has experience and he knows what the disease looks like on the roses he grows. With what he has learned, he continues to grow roses and to enjoy them. In 2001 I asked him to approve the summary above. He replied, "What you have written about me is essentially correct. However, I have mellowed just a tiny bit this spring. If the noted infection is "slight" and the bush is big and otherwise healthy, it becomes more like 3 strikes and you're out. Usually, though, the disease strikes with great force and much of the bush is covered with witches' broom and obvious abhorrent growth quickly." " ----------------------------------- Still in Chapter 4: "I also believe there may be a seasonal element to the success of one strike and you're out. If, and I emphasize If, all the nutrient flow is one directional: roots TO leaves, then cutting a cane may work. If there is a continuing flux-with nutrient interchange roots to leaves to roots on a daily basis then no amount of cutting back may work. We are currently watching our plant of 'Charles Austin' which showed RRD symptoms (Figure 1) at the tip of one cane. We cut the cane off at the base within five minutes of seeing the ugly red growth. We are closely watching the area where the cane was cut next to the soil. I estimate that the growth happened in two days. We seem to have saved the bush; two years after we saw the "rooster tail" the rose remains symptomless." ----------------------------------- Still Chapter 4. "By not removing roses that were known to be infected and trying to allow the maximum bloom from each bush, the entire garden was lost. A garden under this much disease pressure could possibly survive, but I wouldn't even use the "one strike and you're out policy". I would immediately remove suspect plants, which is what happens in our garden (under very low disease pressure) where we have had one half of one percent RRD loss. Something we don't do in our garden, premptive spraying with Cygon, would be advisable under the high disease pressure conditions to which the LMU garden is subject." ----------------------------------- In Chapter 5: " One of the things we have tried to do this summer is to devise a list of subtle early symptoms that would alert a gardener to keep an eye on a particular rose and to know when to spray the mites to prevent potential spread from a suspect bush while it is under observation. This would reduce the chance of over reaction and killing healthy bushes simply because of a blind shoot or other false symptoms." Ann summarises in a FAQ: "FAQ - How do you treat an infected garden": "How do you treat an infected garden? The best course of action if you are convinced one of your roses is infected is to first spray the area with Cygon 2E, then rogue it out and burn it (or bag it and send it to the landfill), and keep a sharp lookout for additional symptoms on other plants, especially on plants adjacent to and downwind of the infected plant. If you have the option, remove any wild roses that might be a source of infection. If you have a rose that is "iffy", that is, it might be sick, but you really don't want to rogue it out, then you may want to place it in isolation. The isolation can be chemical (spray often to make sure no mites from it travel to other roses) or physical (dig it up and keep it away from other roses.). One way that we live with the threat of RRD is to space bushes far enough apart that we can see the individual canes and try to keep canes from one bush from contact with other plants. (This is just hypothetical in our old garden rose beds.) When in doubt, it�s better to dig up, isolate and closely observe a single infected plant. See Chapter 4 for more information." http://www.rosegeek.com/id32.htm --------------------------------------------- H.Kuska comment. One of the advantageous of internet "publication" is that the article can be updated as additional information becomes available. My web page information is at: Here is a link that might be useful: My rose rosette web page

The following was stated: " Reducing the severity of the symptoms....so we can keep sick plants around waiting for additional vectors to find them and spread it? Balderdash" H.Kuska comment: It is my understanding that there are roses that are resistant to natural in field infection. What does this mean? Some observations may be due to the mites not recognizing the leaf surface as belonging to a rose. We do not have to worry about these spreading the infection as they were never bitten. However, what about the others that were bitten but were able to control the infection naturally? Are they going to be "Typhoid Marys" of the rose world? This appears to be a concern of the above quote. My first thought is that the "surviving rose" may have a virus concentration below the amount necessary to overcome most clean roses' natural defense system. The virus plant world is not black and white. There are plants that do not get infected by a particular virus (complete resistance). There are plants that exhibit partial resistance, and there are plants that exhibit so little resistance that the virus kills it. If we add an external chemical that boosts the immune system of a plant so that the plant does not die from the infection, are we providing the plant the opportunity to "fine tune" its immune system naturally so that it will be able to fight the virus in the future without addition application of the external chemical? The literature supports this possibility. This is called systemic acquired resistance against plant viruses. https://www.google.com/webhp?hl=en&authuser=0&gws_rd=ssl#q=systemic+acquired+resistance+against+plant+viruses&newwindow=1&hl=en&authuser=0&start=90 Can this plant that has acquired SAR pass it on to the next generation? Evidence is now being accumulated that supports the possibility of "next-generation systemic acquired resistance". http://www.plantphysiol.org/content/158/2/835.short http://scholar.google.com/scholar?hl=en&q=%22next-generation+systemic+acquired+resistance%22+against+plant+virus&btnG=&as_sdt=1%2C36&as_sdtp= https://www.google.com/webhp?hl=en&authuser=0&gws_rd=ssl#newwindow=1&hl=en&authuser=0&q=%22next-generation+systemic+acquired+resistance%22+against+plant+virus

I have earlier given a link to another thread where I discuss the results on neighboring roses of applying RoundUp to test roses. Since each thread will scroll off of this forum at a different rate, I feel it is appropriate to put that information into this thread. " To test for the occurrence of root grafting, experiments were conducted using the systemic herbicide Roundup®. Plants that were treated with the herbicide died as expected and approximately 50% of the adjacent, untreated Rosa multiflora ‘Burr’ plants and 10% of the adjacent untreated ‘Dr. Huey’ and ‘Sunflare’ plants showed mild herbicide toxicity symptoms. This could be explained if root grafting had occurred, allowing herbicide to move through the vascular connection between plants. " In the full paper the experimental conditions were given. "The Round-up tests utilized 470 multiflora plants, 148 plants of Dr. Huey, and 98 plants of Sunflare. The multiflora and Dr. Huey were planted approximately 11.8 inches apart (H.Kuska comment: it was not clear to me if they were mixed in the same row or in different rows). The Sunflare plants were planted 3.3 feet apart in rows. Roundup was applied to every other plant. The treated plants all died. About 50% of the multiflora plants showed roundup symptoms. 10 % of the Dr. Huey and 10% of the Sunflare plants showed symptoms." --------------------------------------------------------------------------------------- I would expect that 3.3 feet apart would not be uncommon in many home rose gardens. I cannot post the complete paper because it is copyrighted. However, I can send e-mail copies to a limited number of individual requests under the educational exclusion. My e-mail address is: kuska@neo.rr.com The abstract is at: http://www.actahort.org/members/showpdf?booknrarnr=751_26 -------------------------------------------------------------------------------------- Even the RoundUp label acknowledges that root grafting is a known problem: This is the instruction from the Round-Up label for cut stump applications: "Apply this product using suitable equipment to ensure coverage of the entire cambium. Cut trees or resprouts close to the soil surface. Apply a 50 to 100 percent solution of this product to the freshly cut surface immediately after cutting. Delays in application may result in reduced performance. For best results, applications should be made during periods of active growth and full leaf expansion. PRECAUTIONS, RESTRICTIONS: DO NOT MAKE CUT STUMP APPLICATIONS WHEN THE ROOTS OF ADJACENT DESIRABLE TREES MAY BE GRAFTED TO THE ROOTS OF THE CUT STUMP. INJURY RESULTING FROM ROOT GRAFTING MAY OCCUR IN ADJACENT TREES. Some sprouts, stems, or trees may share the same root system. Adjacent trees having a similar age, height and spacing may signal shared roots. Whether grafted or shared, injury is likely to occur to non-treated stems/trees when one or more trees sharing common roots are treated." http://aggie-horticulture.tamu.edu/syllabi/325/schedule/Pest%20Management/Chemical%20Application%20&%20Safety/Roundup%20Original.pdf --------------------------------------------------------------------------