Henry Kuska wrote:

Cass, concerning your suggestion to publish an article on the subject in the
American Rose Annual: I assume that the U. Calif. Davis research is nearing
completion. I hope that they would then write such an article as they are
the "horse's mouth".

Henry, I can appreciate your reluctance to survey the literature when
such a report is expected shortly. However, the amount of accurate
information in a form readily accesssible to even well-informed
rosarians is quite limited. I would view a survey as a precursor to the
Davis report, which undoubtedly will include several provisos that
"more research is needed." That is the perpetual state of knowledge.

Additionally, there is an unsatisfying air of "Don't worry, be happy"
surrounding the occurrence of rose mosaic virus. Don't we all wonder if
we would need fewer fungicides and in certain parts of the country
suffer fewer winter losses if there were fewer virused plants foisted
on on the public? I was delighted this spring to see Jackson Perkins
offering guaranteed virus free plants....for close to $20 each.

I "expect" that they are preparing something for the conference covering
virus diseases of ornamental plants which is scheduled for 2004. (Often,
researchers try to present their results at conferences such as this one in
order to assure that the work gets maximum exposure among those working in
the field.)

Looking at this list of mosaic viri (see? kits are available)
http://www.dsmz.de/plvirus/elisa_o.pdf, it is no surprise that roses
suffer from mosaic virus. I've seen common weeds in my yard suddenly
show up with mosaic or variagation of the foliage.

I suspect that the 1 to 4 % contagion rate is low. My experience with
both budded new releases and with old roses is not reassuring, more on
the order of 25% than 1 %. That experience has bolstered my interest in
collecting and propagating own root, healthy old roses from very old
homes. I read your information about mosaic symptoms showing up as
early as the 1860's. Whatever its rate of transmission then, it could
only increase with modern transportation and production techniques.
Apart from different rates of contagion for different virii, it seems
obvious that different modes of transmission would have different rates
of success. Add that to different susceptibility of cultivars, and the
landscape gets complicated quickly. But "Don't worry be happy" seems
just simple minded and an abandonment of efforts to improve.

Transmission by pruning equipment is the most obvious concern of most
home gardeners. Not knowing (a) how easily transmissible the viruses
are and (b) how many roses suffer from them without showing symptoms,
may make all efforts futile. There is no way of assuring the
cleanliness of pruners even after washing, dipping and drying,
especially with little more more than strings of protein involved. That
doesn't mean I will abandon those efforts. Disposable pruners? No
pruning? Not likely.

Just my thoughts after reviewing your materials.