Alex Shigo (far right) explaining markings on an Oak section during one of his last symposia.
<a href="//commons.wikimedia.org/w/index.php?title=User:Maxwahrhaftig&amp;action=edit&amp;redlink=1" class="new" title="User:Maxwahrhaftig (page does not exist)">Max Wahrhaftig</a>
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<span class="int-own-work" lang="en">Own work</span>