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Roses come into a garden in many ways.  From traded cuttings to purchased leafed out plants,
different rose growers choose different ways to add to their gardens.  Every new rose brings with it the chance for introduction of new diseases.  Different strains of Black Spot may come in with trades;  rust, even mildew can come in as dormant spores on rose canes. Only when the plant reaches temperature ranges where the fungi grow will the disease appear on the rose.   There is a chance that rose rosette can come in with a new plant.  

A lot of people who find RRD in their gardens ask a version of this question, “I bought a new plant from (fill in a name) nursery last year (or even the year before last).  Did this disease come in with that plant?”  My gut reaction is to tell them it didn’t.  From what I've seen, RRD symptoms show quickly on roses that are planted where there is even light disease pressure.

When I get a new rose, I watch it closely. I watch for any sign of wilting, for new basal breaks, for buds to develop, and after the first bloom, I try to force myself to disbud it to direct growth to roots and canes.  If something is wrong with a new rose, I see it early.  Eight years ago I had a bareroot ‘Geisha’ that produced blooms with petals that were terribly wrong: some petals were pink and some were white, and the petal edge had three lobes- almost like a cartoon dragon tooth.  I still don’t know what was wrong with it, but I rogued it out because I didn’t want it near my other roses.   I think most rose fanciers watch their roses closely and would see aberrant growth the first summer, if the plant were infected.  Many rogue out sick plants without getting a diagnosis-they know something is wrong and don't want it to spread.

There is little evidence from the ‘real world’, i.e. gardens, as to the time it takes a bush to become
infected with RRD.  At  LMU, I saw signs of infection on newly planted HTs (that had been
green-house grown from bareroots) four weeks after they were planted downwind from a field of 'R.
multiflora' that was severely infected with RRD.  All six HT’s bloomed, but not very well, as the
infection spread in the plants from cane to cane and finally to the roots. The curator tried to finger prune off the sickly growth but RRD was always ahead of him.   Infection happened fast.

My feeling is that if a rose blooms normally on all canes for a first bloom cycle after it’s planted, then it’s healthy.  This simplification won’t help folks who love once bloomers or roses that may be slower to establish themselves and only bloom in their second year.  Our once blooming roses and other old garden roses that may take a year to establish themselves do put on great growth the first year, and with distinctive cane growth pattern, aberrant growth will stand out even when there are no blooms.  I can’t say, however, that all recently bought  roses are free of RRD

In one month I heard from two people who believe they saw roses exhibiting symptoms of RRD in
nurseries in Tennessee in  2000. One nursery was near Memphis; the other nursery was in east
Tennessee.  In both cases the rose growers tried to warn the sellers; both were ignored. In one case the seller finger pruned the aberrant growth off, so the plant would look good as it remained for sale.
Someone probably bought that rose, took it home, and planted it.  With luck, it died quickly, doing the least harm.  If they were unlucky, it lived and remains infected and is spreading infection into other roses and maybe even into our roses.  

Logically, why would a nursery fingerprune basal breaks before sale?  Why would they remove ‘new’ growth if they thought the roses were healthy enough to sell unless they are ethically challenged?  The problem is that an enraged rosarian has no power. One option is to buy the rose and take it immediately with the sales certificate, to the State Department of Agriculture for diagnosis and to have the dealer inspected more closely.  Then demand your money back.

Another even more disturbing example of good intentions gone awry comes from central Tennessee,
where a number of potted up and grown for 2001spring sale roses showed reddish purple aberrant
growth on two year old bushes.  Someone saw this and was horrified.  A  nursery worker said those
weren’t the only plants that showed that kind of growth, but a customer had brought it to their attention and told them they should finger prune the aberrant growth.  They did.  

By spring  2002  RRD had become more common in 'R. multiflora' along fence rows near Knoxville. TN. Perhaps the most disturbing site is beside I-640 , the beltway around Knoxville which is close to the garden centers of Walmart, Lowe's and Home Depot all of which sell leafed out roses in pots, ready to plant in local gardens. This is shown in the picture below.  By June , mite activity is well established; I think our problems can begin in May when we get our first 90F temperatures.  There is NO legislation that requires RRD-infected plants be removed from the vicinity of rose sales. The phrase 'buyer beware' applies now and leads me to decide where I buy roses and where I won't.

At left: This photograph was taken in May 2002 across the street from the garden center at a local Walmart.  This situation should create a problem for retailers, but most garden center managers are totally unaware of it.  The mass of stems  (witches' broom) emerging from a single cane of  RRD infected 'R. multilflora' in the foreground is a typical symptom - witches broom. The stems have discolored,  leaves of very thin shape and short internodal spacing. Elsewhere, along the same fence row, there are bushes of 'R. multiflora' with buds with aberrant sepals that did not open as well as aberrant leaf forms and stem development.  In this one hedgerow there were at least four large RRD-sickening multifloras that were healthy last summer.  In summer 2003 RRD had spread further but none of the infected bushes had died.

This brings us to mail order roses.  When your garden is in an area with known RRD infection and the nusery isn’t, the answer is pretty straight forward.  Nurseries engaging in interstate shipment of roses are inspected by state agents of the Departments of Agriculture.  There is no way every plant can be inspected, but they do what they can.  Responsible companies also inspect their own operations.  The following is from Dr. Keith Zary of J&P/Bear Creek:   

        “I confirm that to date [May 2001] commercial growers in the Wasco area of California have
        not seen RRD.  I have walked many acres this spring and my crews have covered the entire
        crop to complete our virus inspection.  I do not believe the disease or the vector are in the
        valley. ... I know that our company is very concerned about the disease at both the consumer
        and the grower level.”                                                                     Used with permission.

These problems work both ways.  The seller can also get the short end of the rose cane. A problem
developed in September of 2000 when an ARS Consulting Rosarian (CR) posted on an Internet forum that a particular nursery had knowingly sold RRD infected roses.  Overnight a campaign emerged against the nursery.  The CR’s choice to give advise to someone far away in a state and region in which he had never grown roses didn’t help matters.  

It started when a novice rose grower sought help on the internet because she was worried about strange new growth on a bare root rose she received in the spring of 2000.  The CR suggested she contact the seller.  Someone at the nursery totally unfamiliar with RRD answered her questions and thought she was asking about a different rose disease with different symptoms (Rose Spring Dwarf), thus muddling the issue further.

Based on this misunderstanding, the implication of the CR's post was that the nursery had cut off
infected material and then knowingly sold her the infected plant. That could have been disproved
without much fuss, but certain factors were overlooked.  First the plant bloomed normally after it was planted bareroot in the ground.  Second, the rose in question was planted  in a county immediately south of one that has had RRD in wild roses for over 20 years. Third, the CR directed her to call the nursery and ask about the presence of rose rosette in their growing fields, but they have no growing fields. The nursery in question sells mail order roses that they have bought and sold as dormant plants.  They never see the roses leafed out.  What roses they don't sell, they then pot up and sell to walk in customers ONLY.

Their catalog, web site, and  the Combined Rose List all indicate that they ship ONLY bare root roses which they have received already dormant from their suppliers. There are few, if any, RRD vectoring mites in coolers and that nursery never sees the plant in a non-dormant condition for any buyer outside of their home state. Only as bareroot shipping season ends are the roses potted up for local sale.  How could they have diagnosed RRD in a dormant plant, especially one that had been pruned for shipping?  

Days after the initial post, test results (visual examination) came back and confirmed that the rose had rose rosette. The rose in question was found to have been growing in west Arkansas. Many posts on the same forum have discussed the problems people in Missouri have with rose rosette, and problems in northeast Texas have also been discussed on that same forum.  RRD infected roses from that part of Arkansas had been described in scientific literature since 1983, but a nursery in a non-RRD area was accused of shipping a sick rose into an area with known RRD.  

There is no way to prove where or when that rose was bitten by a RRD carrying mite. The rose’s
owner was new to roses, and the local CR she contacted knew nothing about RRD.  She later reported that her county agent said it looked like rose rosette (implying familiarity with the disease) but that none had been reported from her county. The CR from far away did not address the possibility of local infection.  In the end, the nursery agreeded to replace that rose and any other roses that might become infected with RRD in her garden.

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