Fig. 6.4. Left: An incipient cat-faced scar forming on a red pine in Itasca that was scorched by prescribed fire during spring 1998. Ips bark beetles are colonizing the scorched side of the tree that was on the downwind side of the fire. The attacks are being restricted to this region of the tree by copious resin flow around the periphery of the scorching. Nonetheless, about half the circumference of the tree has been girdled as a result of the fire and beetles. If the tree lives, this damaged area will be evident as a cat-faced scar (Fig. 6.5, left), which will increase the vulnerability of the tree to subsequent fires (Fig. 6.5, right). Right: bark beetle galleries within the phloem of a red pine that was experimentally scorched. The cambium is dead within the infested area, so further tree growth in this region of the bole would be impossible. Note how the phloem has beome impregnated with resin in the region of attack, which appears to have limited the extent of the beetle galleries.
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