Technical Abstract: Ambrosia beetles pose a significant challenge to producers of ornamental nursery stock. Conventional insecticides are commonly used for management purposes, but botanical formulations may also discourage ambrosia beetles from initiating attacks. In order to identify promising formulations, field-based efficacy trials were conducted in Ohio, USA in 2009 and 2010 with the following commercially-available botanicals: Armorex (Soil Tech.), Cinnacure (Proguard Inc.), Ecotrol (EcoSMART Tech.), and Veggie Pharm (Pharm Soln.). Based on previous studies, potted Magnolia virginiana L. were first injected with 75 ml of 5% ethanol to increase host attractiveness and ensure ambrosia beetle pressure. Botanical formulations or a water control were then applied until runoff and attacks occurring under field conditions were quantified at 1, 4, 7, and 14 days after treatment (DAT). Ambrosia beetle attacks generally increased over time, but at differing rates depending on the particular treatment. In 2009, Veggie Pharm and Armorex were associated with the lowest cumulative attacks 14 DAT. In 2010, Armorex and Cinnacure were associated with the fewest attacks 14 DAT. Solid phase microextraction-gas chromatography-mass spectrometry was used to characterize the volatile organic compounds associated with each formulation. Allyl isothiocyanate, a compound with known repellent and insecticidal properties, was unique and predominant in the comparatively effective Armorex formulation. These experiments assisted with identifying certain botanical formulations with potential for managing ambrosia beetles, along with demonstrating the usefulness of ethanol-injection to ensure pressure on experimental trees under field conditions. Identifying the constituents of bioactive formulations will assist with identifying key components contributing to activity.