Raffaelea lauricola

The detection of laurel wilt in redbay and sassafras is usually straightforward with wilted and dead foliage occurring in some branches initially and eventually over the entire crowns of trees (Fraedrich et al., 2008). A black discolouration is observed in the sapwood of stems and branches. Initially, the discolouration is primarily evident in the outermost sapwood but as the disease progresses the discolouration will be observed through much of the cross-sectional area of the sapwood. Isolation of the pathogen from infected tissues on agar media is necessary to confirm the disease diagnosis. Frass tubes are typically observed on stems and branches of redbay and other species being attacked by X. glabratus, and frequently these are numerous after trees have wilted.