Hello. We have three adjacent pyracanthas at rear of house (northeast US),
that have been very large and hardy for at least 7 years. Grew like weeds.
Some branches 15 feet high. Now a few major limbs are dying. All three
plants. No apparent scale, no evidence of borers on bark or in soil
beneath. The only possible factor I can think of is that we did some
aggressive pruning last spring without "sealing" the cuts. Garden supply
guy says that should not have caused it - not necessary to seal pruning
cuts.

Garden supply guy says to prune dead limbs, sterilizing shears in alcohol
between cuts (is that neessary?), then use a growth supplement for soil that
supposedly strengthens the plants defenses against fungus, etc. (The
product is called Messenger. Active ingredient listed as "Harpin Protein".)

I'd appreciate any other insights.

Thanks, Ron

On Tue, 27 Sep 2005 10:10:07 -0400, Ron wrote:

> Hello. We have three adjacent pyracanthas at rear of house (northeast
> US), that have been very large and hardy for at least 7 years. Grew like
> weeds. Some branches 15 feet high. Now a few major limbs are dying. All
> three plants. No apparent scale, no evidence of borers on bark or in soil
> beneath. The only possible factor I can think of is that we did some
> aggressive pruning last spring without "sealing" the cuts. Garden supply
> guy says that should not have caused it - not necessary to seal pruning
> cuts.
>
> Garden supply guy says to prune dead limbs, sterilizing shears in alcohol
> between cuts (is that neessary?), then use a growth supplement for soil
> that supposedly strengthens the plants defenses against fungus, etc. (The
> product is called Messenger. Active ingredient listed as "Harpin
> Protein".)
>
> I'd appreciate any other insights.

Sounds like fire blight. Google "disease pyracantha". Plant
something resistant. daveA

>
> Sounds like fire blight. Google "disease pyracantha". Plant
> something resistant. daveA
>

Thanks for the reply. After additional research, fire blight is my guess
also, although I don't see the (supposedly) characteristic curling of the
leaf shoots that I saw in one picture on the web. Not ready to give up on
these plants, though. There are still several healthy major branches.
Gonna prune deadwood, with sterile rinse between cuts, and use that
Messenger product in the spring.

I'd been googling on "dying pyracantha". Your string is much more
productive. Thx again, Ron