In chapter one of this thesis, the seasonal timing of Nitidulidae beetle activity and contamination by the fungus (Bretziella fagacearum) that causes oak wilt were monitored, along with development of red oak xylem vessels. Activity for all species was highest in May and June, which coincided with the main contamination period. Of the 23 nitidulid species captured, six were found to be carrying viable B. fagacearum spores. In chapter two, volatile organic compounds (VOCs) associated with oak wilt were collected and identified from samples of healthy, unwounded red oak trees, healthy red oak trees with a fresh wound, B. fagacearum mycelial mats on dead red oak trees, and pure colonies of B. fagacearum grown on Petri dishes. Identity and abundance of compounds differed among sample types. Compounds that were especially abundant and characteristic of each sample type could be potentially useful for future lure development. In chapter three, I evaluated survival and growth of red oak trees in 22 provenances in a plantation at MSU’s W.K. Kellogg Experimental Forest in southwest Michigan. These trees were planted in 1962-1963 and were 55-56 years old at the time of evaluation. Survival differed among provenances; all trees from three provenances had died by 2018. Overall, 17% of the trees originally planted in the plantation remained alive in 2018. Diameter at breast height (DBH) and height of trees did not differ among provenances.
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