Damage and mortality data are collected as part of the US Forest Service, Forest Inventory and Analysis (FIA) ongoing assessments of the nation's timberlands. The usefulness and value of FIA tree data in assessing historical levels of oak decline and oak mortality were investigatedfor seven Midwestern states. The data were collected during two periodic inventories conducted between the early 1970s and the mid-1990s. One-tenth to one-third of the oak trees had decline-associated damage in a given inventory, but no trends over time were apparent across the states. Thepercentages of dead trees ranged from less than 1 to 11 across all inventories and states; mortality was higher in the late inventory than the early inventory for all states. This is the first reported attempt to quantify oak decline across the Midwestern Region and it was accomplished using FIA tree data. The major concerns of the approach used are the subjective nature of the damage codes used to tabulate declining oaks and the inconsistencies and inherent subjectivities in the FIA recorded codes. The major drawback for non-FIA researchers is the time required to understand the intricacies of the FIA system.

Effectiveness of oak wilt control actions taken between 1997 and 1999 were evaluated for an urban forest park reserve in Minnesota, U.S. A high level of success (84% of evaluated disease centers) was achieved in controlling belowground spread of the vascular pathogen for four to six years by mechanically disrupting inter-tree root connections with the blade of a cable plow (vibratory plow, VP). Placements of the outermost (i.e., primary) VP treatment lines were based on a modified, rule-of-thumb model. Plausible scenarios based on two protocols for preventing pathogen spore production, and thus aboveground insect-mediated spread, were explored in conjunction with alternative, root treatment models using a geographical information system. For the 95% confidence level of a statistical model, the numbers of red oaks inside primary lines were 2.5 times greater than those inside the primary, installed lines and represents the difference in tree losses if all red oaks were removed to the primary lines [i.e., a “cut-to-the-line” (CTL) protocol]. Alternatively, a “monitor and remove” (MR) option (i.e., annual removal of wilting red oaks), would have resulted in 64% fewer removals than CTL. The park’s forestry division subsequently added the MR protocol to its oak wilt control program.