Fig. 5.1. Mature red pines at Itasca State Park that were under attack by Ips bark beetles during 1998 (left and middle). Note the presence of branches with red, dying needles intermixed with healthy branches. Contrast with the uniformly thinning crown of the tree on the right, which was not infested with bark beetles (possibly infested with Diplodia blight). The tree on the left, 704 in Table 5.1, was dead in 1999. The middle tree, 720 in Table 5.1, was sustaining continued attacks in 1999.
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