Brian,
Thanks for the insight into my problem. The last few summers here have been
dry, and the soil was well drained. I found an ant infestation at the base
of the tree, so they may have played a role in its demise. There is a
fungus circle about 50 feet north of the tree site, but I saw no evidence of
a connection. Another of life's puzzles.
Jim Nichols
Tullahoma, TN USA
----- Original Message -----
From: "Brian Swale" <bj@xxxxxxxxxxxxxxx>
To: <olympus@xxxxxxxxxxxxxxxxx>
Sent: Wednesday, September 16, 2009 10:20 AM
Subject: Re: [OM] IMG: Death of an Oak Tree
> Re: Jim Nichols' oak tree,
>
> I am a forestry professional by training with a Masters degree in the
> field,
> and for a good part of my paid employment I had significant
> responsibilities
> in the area of forest pathology, though in the field of forest pathology
> on a
> forest scale rather than on an individual tree scale..
>
> In my opinion, while a reading of stem density (we never had such clever
> devices in 'my' day) can give an indication of decay or other solid wood
> loss
> in the zones assessed, the important indicator that Jim also mentioned is
> leaf health during the growing season. For oak leaves to curl at the
> edges
> and become prematurely brown indicates to me that there is at least one
> pathogen of some sort (be it fungal, bacterial, viral nematodes; or
> insects; or
> even a high level of soil water (drowned roots)) seriously interfering
> with
> either the cambium layer in the lower stem / roots, or the roots
> themselves,
> so that the tree is being starved of water and/or nutrient supply. Yes,
> trees
> with hollow centres can be very strong, if a slow wood rot fungus is the
> only
> pathogen at work, but clearly in the case of Jim's tree something else was
> at
> work too.
>
> There are many people in the USA who are skilled in assessing what are
> called "hazard trees" in parks and other areas of high human use, and
> there
> is a substantial literature on the topic.
>
> I reckon that Jim had little other option than keeping ahead of the game
> as
> he did in this instance.
>
> Brian Swale.
> --
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