Dying Canes and Fungicide
Sorry hit send too soon.
I know of atleast 2 varieties
of canker on my roses.
The tip variety is relatively harmless.
Just cut back to clean cane.
The other one I've seen occassionally
causes black/purple spots with a whitish
raised ridge around it.
This causes loses of entire canes for me.
I've only seen it a couple of times.
I'm not sure what variety it is. I didn't mess
around with fungicides but rather cut the
entire cane away. Ouch!
--
Theo in Zone 5
Kansas City
"Theo Asir" wrote in message
news:e9499bf02edc4b826b787b4a3e6a1a1e@TeraNews...
Julie, I have not had the
pretty extensive damage you are
seeing. But I've seen a lot of
damage caused from spraying in high
heat when the roses is transpiring the most.
Its the heat not the sun that causes damage.
As I noted earlier My cornell
mix does this unfailingly.
As far as the least resistance to BS correlation
I can't imagine it.
In my experience most tip die back begins with the
roots. If the roots are not collecting enough nutrients
the rose begins cutting back on cane.
--
Theo in Zone 5
Kansas City
"Unique Too" wrote in message
...
Dave wrote:
The thing that alarms me is a purple "bruising" on the stems of Old
Blush,
Several of my roses are having a similar problem. The canes develop
purplish
spots, then the cane turns yellow with spots and then dies. This
condition
develops not on the small end branches, but on either a main cane or
lateral.
When the cane starts to go, the tips of the branches above the cane with
start
dying, looking like dieback. From spots to dead isn't long, a week or
two
at
the most.
If it is dieback or canker, fungicides should help. When I first
noticed
it, I
began spraying more regularly, but I have never used Banner Maxx more
often
than 14 days.
I must wonder if the problem is not a lack of fungicide but the result
of
fungicide, specifically Banner Maxx. I never had this problem until two
years
ago, a few months after I started using Banner Maxx. The only roses
affected
are those that are sprayed and all the sprayed roses, except Rose de
Rescht,
show the same symptoms. I've read other posts, on other boards, where
dieback/canker/whatever is becoming more of problem than ever before.
And
I
believe more people are using Banner Maxx, it seems to be the current
favorite.
I'm not accusing Banner Maxx, I'm not convinced it is the problem, but
I
do
wonder. It could be the roses least resistant to BS are also the least
resistant to whatever is causing this problem. I've stopped spraying
the
two
roses most affected, they are down to one cane already. Since I expect
to
loose them anyway, they are my test roses. If the situation improves on
these
two roses, I'll start spraying again, but not with Banner Maxx and see
what
happens.
Anyone else having the same/similar problem?
Any comments?
Julie
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