Effects of temperature on ethanol pouch types and ambrosia beetle capture

Ambrosia beetles are the most important wood-boring pests in ornamental nurseries. Ambrosia beetles use ethanol signals to locate stressed trees and attack those trees. Ethanol is also utilized to develop monitoring tools as it provides flight activity of ambrosia beetles in nurseries. Various ethanol pouches are commercially available for growers; however, ethanol release rate and how they interact with ambrosia beetles in nurseries are still unclear. Thus, the objectives of this study were to determine 1) the ethanol release rate of common ethanol lure pouches under various temperatures and 2) the captures of ambrosia beetles in nurseries. Three ethanol lures were studied and they were: 1) AgBio low release [AGL], 2) AgBio high release [AGH], and 3) Trécé lure [T]. Ethanol release patterns were at 15.6, 21.1, 26.7, and 32.2 °C. Data show that a significantly greater amount of ethanol was released at 26.7 °C than at the remaining temperatures, regardless of lure types. In 2022 and 2023, these three lure treatments were deployed in nurseries and ambrosia beetle captures were quantified. In 2022, ambrosia beetle captures were significantly greater for the AGL treatment than for the AGH and T treatments.