Damaging ambrosia beetles (Xylosandrus germanus and Xylosandrus crassiusculus) are attracted to and preferentially attack stressed trees emitting ethanol. Ambrosia beetles bore into the xylem of trees excavating tunnels (galleries). Stressors such as flooding induce trees to produce and emit ethanol. Flooding is one of the most common ethanol-inducing stressors occurring in tree crops. In previous research, ambrosia beetles attacked flood stressed trees within 2 days of initiating flood conditions and offspring were present in galleries (successful colonization) after 15 days of flooding. However, whether ambrosia beetles can successfully colonize trees after short-term flood events (more common than long-term) is unknown. The current research examined colonization success (offspring produced) by X. germanus and X. crassiusculus on trees flooded for various periods of time (days). Successful colonization was more likely as the number of days flooded increased. Trees flooded for only three days were readily attacked, but the attacking beetles were often dead or missing and offspring were rarely found. Furthermore, attacked trees flooded only three days were able to survive through the following spring and blossom. This research indicates growers may not have to cull trees attacked during short-term flood events.
