It was unknown whether twolined chestnut borer, Agrilus bilineatus (Coleoptera: Buprestidae), a common secondary agent of tree decline in eastern US oak forests, contributed to tree mortality during a recent (1999–2003) episode of oak decline in the Ozark Mountains. Adult beetle flight was monitored by trapping in 2001, 2003, and 2004 and oak branches and trunks were visually examined for exit holes and dissected to examine larval galleries. Very few A. bilineatus adults were found each year by trapping (< 10 as opposed to > 100 red oak borers [Enaphalodes rufulus; Coleoptera: Cerambycidae]), and no evidence of A. bilineatus was found in 70 dissected tree boles or in upper crown material, although other buprestids (Chrysobothris femorata) were noted.