Spatio-Temporal Analysis of Xyleborus glabratus (Coleoptera: Circulionidae: Scolytinae) Invasion in Eastern U.S. Forests

• Published in: Environmental entomology 2008-04, Vol.37 (2), p.442-452
• Main Authors: Koch, F. H, Smith, W. D
• Format: Article
• Language: English
• Subjects: ambrosia beetle; ambrosia beetles; Animals; Biological and medical sciences; climate matching; climatic factors; Coleoptera - physiology; Community and Ecosystem Ecology; cost-weighted distance; Demography; ecological invasion; Ecosystem; forest pests; Fundamental and applied biological sciences. Psychology; geographical distribution; host plants; invasive species; Persea; Persea borbonia; pest infestation; Phytopathology. Animal pests. Plant and forest protection; plant density; Protozoa. Invertebrates; Records, symptoms, damages, economic importance, population surveys; redbay; Sassafras albidum; spatial distribution; temporal variation; Time Factors; Trees; United States; Xyleborus; Xyleborus glabratus
• ISSN: 0046-225X; 1938-2936
• DOI: 10.1603/0046-225X%282008%2937%5B442%3ASAOXGC%5D2.0.CO%3B2

The non-native redbay ambrosia beetle, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), has recently emerged as a significant pest of southeastern U.S. coastal forests. Specifically, a fungal symbiont (Raffaelea sp.) of X. glabratus has caused mortality of redbay (Persea borbonia) and sassafras (Sassafras albidum) trees in the region; several other Lauraceae species also seem susceptible. Although the range of X. glabratus continues to expand rapidly, little is known about the species’ biology and behavior. In turn, there has been no broad-scale assessment of the threat it poses to eastern U.S. forests. To provide a basic information framework, we performed analyses exploiting relevant spatio-temporal data available for X. glabratus. First, we mapped the densities of redbay and sassafras from forest inventory data. Second, we used climate matching to delineate potential geographic limits for X. glabratus. Third, we used county infestation data to estimate the rate of spread and modeled spread through time, incorporating host density as a weighting factor. Our results suggest that (1) key areas with high concentrations of redbay have yet to be invaded, but some are immediately threatened; (2) climatic conditions may serve to constrain X. glabratus to the southeastern U.S. coastal region; and (3) if unchecked, X. glabratus may spread throughout the range of redbay in