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- From: "loneroc" <loneroc@mwt.net>
- To: "North American Fruit Explorers" <nafex@lists.ibiblio.org>
- Subject: [NAFEX] Swiss Stone Pine Plague
- Date: Wed, 18 Jul 2007 06:11:03 -0500
Howdy all,
Last year one of my 20-year-old, 15 foot
tall Pinus cembra started to die in midsummer, a branch at a
time. The branches sort of dried up, starting in one area of the tree and
'spreading' to adjacent branches, keeping greyish-green needles shriveled
on them until the needles browned a month or two later. The branches seemed to
start dying on the south side of the tree. I cut branches off the
trunk as they died but went ahead and removed them all of them after there were
only a few left on the lower north side of the trunk, leaving the bole standing
as 'woodpecker fodder'. Diversity is good you know--but I probably made a
mistake in hindsight. I figured the death was a fluke---but I was
wrong.
Now the two adjacent trees have started the same
process, though the initial branch death is confined to a few more randomly
scattered branches. I am not an expert in pine diseases, but I wonder if
there is some sort of boring insect feeding away on my prize pines. If I
recall correctly Pinus cembra is not subject to White Pine Blister
Rust--the symptoms are different and anyway one would suspect that my dozen
White Pines would have succumbed first. I noticed two 45-year-old Red
Pines on my property looking pretty skanky the last few years with the loss of
many smaller branches. I figured at least one of them would succumb at
some point but it's hanging on. Since the branches are high up I haven't
really noticed whether the branches whither before turning rusty but I wouldn't
be surprised if the problem were the same.
The Swiss Stones are not stressed--they get water
regularly here in my sand-trap. If it were only a question of the
pine nuts, it would be no loss, since the cones are always blanks. But the
trees are beautiful, and I need every bit of shelter I can get here in the
desert (SW Wiscinsin, alkaline sand). What's happening? Am I too
late to save them--especially if I don't know what's going on for sure? I
haven't yet stripped the rest of the bark off the dead bole to see whether I can
spot the tell-tale tunnels of a borer--maybe there are patterns specific to a
particular borer species? I'm not sure what evidence will remain as
the woodpeckers have actually stripped off quite a lot of the bark in the last
year--maybe their rapid attraction to the dead tree means that there were bugs
awaiting their immediate attention.?
If there are borers, I'd be willing to spray if
it's not too late. I have some Cygon left that I used to use on orchid
scale before I started using Enstar, an insect hormone product. I've got a
15-year-old bottle of Lindane in my garage that I assume that the previous
owners used on their two Macs and two Cortlands (only one of the original trees
is left after a -45F freeze). The Cygon is a systemic--I don't know what
the Lindane's mode of action is. Maybe pesticides age like fine wine
and the Lindane would now be purrrrrfect for any imaginable pest
problem;-)?
I'd consider cutting them down to try and protect
my last two symptomless Swiss Stones, but if there is a gigantic Red Pine
resevoir here I'd be better off taking my chances on Mr. Darwin's solution to
disease problems.
Help!
Steve Herje, SW Wisconsin USDA zone 3
|
-
[NAFEX] Rhubarb,
Jim Fruth, 07/04/2007
- <Possible follow-up(s)>
-
Re: [NAFEX] rhubarb,
Deb Schneider, 07/04/2007
-
[NAFEX] Swiss Stone Pine Plague,
loneroc, 07/18/2007
- Re: [NAFEX] Swiss Stone Pine Plague, Mark & Helen Angermayer, 07/19/2007
-
[NAFEX] Swiss Stone Pine Plague,
loneroc, 07/18/2007
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