"Theo Asir" writes:

So I went looking and this is apparently
not very well known but Downy Mildew apparently
causes these blotches on rose canes.
I couldn't even find a good picture but
try this one.

http://www.cruzio.com/~rbedard/devor...wnymildew.html

The last two photos of the leaves sure look familiar to me. I even brought a
couple inside so I could look at the leaf and photo at the same time. I think
you might have found the answer.
I've always used Dithane M-45 as one of my fungal sprays. All the articles I
found mentioned it was effective against DM. When I started using Banner Maxx,
I began using the Dithane less often. So that fits with my blaming Banner
Maxx.
It also mentions high humidity being a requirement, we certainly have plenty of
that here.
One of the non HT roses affected does get a lot of shade. The other non-HT,
Belinda's Dream is so very thick and full, even growing alone it can't possibly
get good air circulation.
I think I'll go back to using Dithane as my primary fungicide and see what
happens. Of course our temps stay in the upper 80's now so I should notice a
decrease anyway.
Maybe you're right again, Theo. Maybe...

One of the non HT roses affected does get a lot of shade. The other
non-HT,
Belinda's Dream is so very thick and full, even growing alone it can't
possibly
get good air circulation.
I think I'll go back to using Dithane as my primary fungicide and see what
happens. Of course our temps stay in the upper 80's now so I should
notice a
decrease anyway.

All that I have read on this disease calls
for fairly dramatic action. The author of that
page called for abandoning the spray schedule
and essentially a slash and burn technique.

From my sisters experience with her grapevine
(she lost everything) this not a disease
like PM or Blackspot that can
be tolerated. It MUST be erradicated. Quickly.

The disease once inside the plant will
continue to kill it, roots & all. Climate
has little influence at that point.

--
Theo in Zone 5
Kansas City

Maybe you're right again, Theo. Maybe...

Unfortunately so.

Shiva,

Two things -- First, you might think about using Roundup on the "garbage
shrub" as some things really *thrive* on being hacked up (think classical
myth where 9 snakes sprang up from each one that was slain) -- my husband
once created the most gorgeous 3' square thistle by attacking it with a weed
whacker! (Served him right -- he was supposed to leave thistles alone
because the goldfinches depended on them for nesting material.)

Second, if it's any consolation to you, the voles in my yard prefer
unmulched soil 95% of the time over the areas mulched with shredded bark.
Either that, or they're really getting good at hiding the holes under the
bark

Also, "disturbing" the oak leaf mulch might be enough to keep it from
collecting enough moisture for the mosquitoes.

Anne Lurie
Raleigh, NC


"Shiva" wrote in message
s.com...
On Mon, 30 Jun 2003 15:10:39 GMT, "Theo Asir"
wrote:


Cass your pictures triggered of
a memory in my head. I saw the same
damage on some grape vines
my sister grows. She told me
was a Mildew. Apparently mildew can
affect canes too.

So I went looking and this is apparently
not very well known but Downy Mildew apparently
causes these blotches on rose canes.

Theo, this is right on. There is a garbage shrub out by one of my
beds, it is really a weed that grows into a tough woody shrub really
fast. Among the many reasons for which I hate it (I have hacked it to
the ground three times), it gets covered with thicky, gaggy looking
white mildew all over its thick, shiny, hollyish leaves. Well--I just
checked and both Tropical Sunset and Pensioner's Voice have that
purple, bruised looking cane and are cankering all to hell.

It has been a great day, my friend. The voles killed my lovely
Sunsprite AND Lover's Lane, and it looks like White Lightnin' might be
half gone. I dug up the ownroot Scentimental beside WL and plunked it
in a pot to see if I can save it from the same. I think it is safe to
say that using thick mulch around here, especially oak leaves, is a
mistake. There was Permatil in every one of those holes, all the way
around the bottom and the sides! I think the little f*kkers went in
from above, instead of below! Wahhhhh! Two weeks ago they got Reine
des Violettes, Granada, and their second Europeana!



I couldn't even find a good picture but
try this one.

http://www.cruzio.com/~rbedard/devor...wnymildew.html

--
Theo in Zone 5
Kansas City


"Unique Too" wrote in message
...
Cass writes:

I don't think it is Banner Maxx. I almost never spray fungicide and
have never used Banner Maxx. I first saw this stuff last year on
Lavender Lassie. Dormant spraying has had no effect, nor have I seen
any decrease since spraying for Fore and with Decree. I suspect that
I'm going to lose the whole plant, which will be a shame. I just sense
that it's headed for collapse. I thought is might be an effect of
spraying myself because it seems to appear down one side of the cane
in
some cases. But then I saw spots on roses that have never been sprayed
at all. I also thought it might be sun burn, but then I found where
the
sun don't shine. However, there are many different kinds of
spots....here's what I find on my rose, which could be a different
gunk:

http://home.earthlink.net/~cbernstei...assieWorst.jpg

http://home.earthlink.net/~cbernstei...assieSpots.jpg


Kind of hard to tell by the photos. I don't see the distinct purple
spots
and
yellow cane that I see on mine. But it may be my monitor not showing
the
true
colors.
I'm pretty certain it isn't sunburn, most of the affected canes are too
low to
the ground to get direct sun.
I've used a variety of fungicides, but the only new one is the Banner
Maxx. In
looking for a cause that was the one thing I could see that I had done
differently.
A nutrient dificiency is another thought. But it's happening in
different
areas in different soil types. Both the good soil and sandy spots have
the
same problems. I haven't changed my fertilizing habits, it's varied,
lots
of
different kinds, mostly organic, but also some cheap bagged stuff.

I bought some Zyban (Cleary's 3336 combined with Fore) because of
Cleary's supposed systemic effect. That's the only thing I can think
to
do. I guess I could also try Phyton 27 for the same reason....


That's two I haven't tried. I did use a copper one this year for the
first
time. An "expert" told me that would help if it were a canker. I
couldn't see
any difference, I still continued to loose canes.


Can you post pictures? I can come up with all kinds of conspiracy
theories if I work myself up, but I think that even in my own garden,
I
have more than one think at work. For example, I think a canker is at
work also, and since it causes cane symptoms, it's easy to confuse the
two. I guess I'm going to have to get a lab test.

I need to take some photos, but I haven't yet. If the weather
cooperates
this
weekend, I'll put that on my to do list.
Lots of strange things happening with the roses lately. Is someone
trying
to
tell me they should go away? Or make me give up? Ain't gonna happen.
Where do you get a lab test? At this rate it would be worth it to save
the
roses or at least know what is going on. I'm not good with things I
don't
understand or can't figure out.

Julie