Rosette Roundup

It's time, my friends, to report the results of the Rose Rosette Plague and Massacre of 2017.  I spent the weekend before last culling out the victims and mourning the holes left in the landscape beds, and there are still a couple of very sick individuals to tackle.  This weekend, I had a brief respite from the slaughter of so many innocent roses while I accompanied Mrs. ProfessorRoush on a short day-long journey.

The Newly Departed, dead or ripped from the ground and cast on a funeral pyre:

Folksinger
Prairie Harvest (2)
Double Red Knockout
Freisinger Morgenrote
Rosenstadt Zweibrucken
Carefree Beauty
Improved Blaze
The Fairy
Kashmir
Hot Wonder
Golden Celebration
Alba Odorata X Bracteata
Morning Blush
Charlotte Brownell
Prairie Star
Hawkeye Belle
Queen Bee
Champlain
Red Moss (2)
Variegata de Bologna
Cardinal de Richelieu
Lady Elsie May
Prairie Sunset
Alchymist
Winter Sunset

These are, mind you, just the roses that were showing Rose Rosette at the end of last year.  I have not kept count, but I've probably lost 50 roses to RRD, or at least 25% of the rose cultivars in my garden.   I have a number of other roses that just failed to return this year, but never showed any signs of Rose Rosette; were they weakened by disease and then finished off in a tough winter?

As far as groups of roses, the Rugosas seem to be the most resistant.  I've only had one, 'Vanguard', definitely affected with RRD, although I'm suspicious of my 'Conrad Ferdinand Meyer' at present (but who could be sure, given its already excessive thorniness?).  Most of my gallicas and albas seem to be resistant to RRD, although hybrids, like 'Morning Blush', are fair game.  The Griffith Buck roses are hopeless.  I've lost most of them, either due to RRD, or due to a combination of subclinical RRD and winter kill.  My remaining Griffith Buck roses are either pretty isolated in distance from the main rose beds, or they are probably living on borrowed time.  For those who are wondering, I don't believe the idea of cutting diseased canes off at their base has ultimately saved any rose and believe me, I tried.  When you see the disease, destroy the plant immediately.

I've filled some of the holes, after an appropriate waiting period, with new roses, primarily Rugosas or OGR's, hoping that they are resistant to RRD.  I just received starts of 'Moje Hammarberg', 'Fimbriata', 'Scabrosa', 'Armide', 'Georges Vibert', and 'Orpheline de Juiliet' from Rogue Valley and planted them today.   I also went on a "sucker" spree last week and transplanted suckers of 'Harison's Yellow', 'Souveneir de Philmon Cochet', and 'Dwarf Pavement' into a number of areas.   I'll probably regret the invasive possibilities of the 5 new clumps of 'Harison's Yellow' if they all live, but not until they get out of hand.  My roses are going to be overwhelmingly yellow and early in a couple of years.

While I was out with Mrs. ProfessorRoush, I acquired the metal rose shown in the photo accompanying this blog entry.  It may be prone to rust (sic), but I'll bet it doesn't become extra thorny nor develop witches broom growths from Rose Rosette Disease.  One way or another, I'm going to have roses in my garden, eh?

Witches' Broom Arrives

The first words in my mind, about three weeks ago, as I discovered the potential disaster pictured to the right, was a horrible parody of Draco Malfoy in the first Harry Potter movie:  "It's true then.  Rose Rosette Disease has come to Hogwarts."  Read that statement with a really exaggerated English accent and you'll know how it sounded in my mind.  Crazy, I know, but somehow I must have neurons cross-firing between "witches' broom" and my mental images of the magical world of Hogwarts to make that connection.  And, yes, I'm a fan of the Harry Potter series, but, no, I haven't taken to calling my garden "Hogwarts."  I don't have a name for my garden.  Come to think of it, "Hogwarts" might be as good as any, but I'm guessing that Mrs. ProfessorRoush won't see the humor in it.


I digress, however, as I try to avoid the awkward subject at hand.  Although I'm not entirely 100% positive, I highly suspect that the misshapen foliage and canes show above are Rose Rosette Disease on my 'Golden Princess' rose.  I suppose there is always some faint hope that this was damage from herbicide drift, but that multi-prickled cane appearance and warped leaves are pretty damning evidence to the contrary.   The canes on this rose should look like the photo at the left, a more normal area of the bush. 

Either because of inborn psychology, or due to my veterinary medical training, I'm not one to wait around and ignore a potentially garden-fatal cancer.  I'm not Scarlett O'Hara in my garden, thinking I can worry about this tomorrow.  In my reading on Rose Rosette Disease, I know that immediate action is necessary to prevent spread to other roses.  Since I grow over 200 other roses, an epidemic of RRD is to dreadful to contemplate, a fear which also helped me take decisive action.

I immediately initiated the "one strike and you are out" philosophy used by other RRD victims.  I have chopped out every cane (yes, with an axe!) that appeared to have any disease and I included the roots of those canes, resulting in the small and normal- appearing remnant displayed to the right.  This rose has one chance, a chance possible only because it is an own root rose and I could divide it without splitting a bud union.  If it shows me any sign of RRD in the near future, then this remainder gets shovel-pruned immediately, day or night, rain or heat.  I know there is no wild multiflora rose within over 0.5 miles, so I don't know how it arrived here except in the Kansas wind, but I'm not going to baby a diseased rose in my garden.

In the interests of rose-related education, if you've never seen RRD, take a good look at that top photo.  Symptoms of RRD include excessive thorniness, leaf malformation, bright red leaf and stem pigmentation, enlarged cane diameter or elongated shoots, and "witches' broom", the latter characterized by a dense mass of leaves and stems growing from a single point.   The causal agent of RRD has recently been proven to be a negative-sense RNA virus in the genus Emaravirus (Laney AG, et al, J Gen Virology 2011:92:1727-1732), that is spread by the Rose Leaf Curl Mite (Phyllocoptes fructiplilus) mite.

One deformed leaf, and 'Golden Princess' is no more.  At least I've got another, ordered last Winter by mistake...or was it by fortuitous clairvoyant foresight?