In article
,
jaygreg wrote:

Where can I find instructions for the proper way to trim this
sensitive tree? My Google searches aren't successful. Every time I try
tinkering with the limbs, the entire branch dies... even when I trim
at a joint.

If you're pruning lower branches, if the rest of the limb is shaded by
higher branches, the shaded branch may well die because it is no longer
fed by sufficient length of foliaged branch. Mine's a hardy tree that
never needs pruning; I got it as a slim but very tall pot-grown tree and
it had lost its lwoer branches from overshading, but has never needed even
one bad limb removed since I planted it a few years ago, and it's now much
taller than our two-story house. Absolutely care-free tree.

I can't help but wonder if your own limb loss is not from pruning but from
the pruning being "one stress too many" and the tree should be checked for
insect stress, borer holes, bark cracks; its watering schedule should be
measured so as to never be too dry during heat-stressing months
(especially a young tree), nor poor drainage in rainy periods. It can have
moisture-stress if overwatered or in soil that drains badly; and the soil
should not be at all alkaline. When to prune is partly dependent on where
you live. Pin oaks generally prefer to be pruned (if at all) in mid-summer
or in winter; the leaf development is very active in spring, roots are
working doubletime in autumn sucking energy back from the leaves, which is
why it stresses them to be pruned spring or autumn -- but check for any
different advice specific to where you live. Winter pruning is easiest for
really assessing the tree's structure, but summer for assessing which
limbs are healthiest.

If it's oozing dark hardening sap at any point it's probably a doomed tree
in slow decline, nothing can be done as that's usually pathogenic. If not
stressed by any other factors it should be easy to give it a high-summer
or winter pruning for shaping purposes without risk of loss of limbs. A
maturing tree shouldn't need any pruning, however, unless a limb craps out
then it should be removed entirely, or unless it has annoyingly tried to
grow with two or three leaders the extras needing removal.

You should check out a library book on pruning if you've any questions;
net advice can be iffy, and since my pin oak thrives without any pruning
at all, I won't even promise my sense of what's best is guaranteed
correct. And there are some niceties of pruning angles and the like that
are easiest to understand with a book that has some drawings on the topic.

-pagaht the ratgirl
--
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http://www.paghat.com
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