Modeling the Spread of Invasive Weedy Species Following Natural Disasters

Prince Czarnecki, J. M., Shaw, D. R., Byrd, J. D., Holly, D. C., Ervin, G. N., Grado, S. C., & Madsen, J. D. (2008). Modeling the Spread of Invasive Weedy Species Following Natural Disasters. Proceedings Southern Weed Science Society. Jacksonville, FL.

Management of invasive species is a multi-faceted problem, involving an understanding of the ecology of invaders and the invaded systems, the economic costs and benefits associated with management approaches for invading weeds, and the societal perception and responses to these issues. A research project was conducted to use a model invasive weed (cogongrass, Imperata cylindrica) to develop a process for constructing mechanistic, predictive models of suitable invasive plant habitat. It was hypothesized that canopy disturbance in managed forests, from natural disasters or anthropogenic factors, would increase the susceptibility of recovering forestlands to invasion by non-native weedy plant species. It was further expected that human-caused disturbance would result in greater degrees of invasion. Results indicated that the majority of cogongrass resulted from anthropogenic disturbance related to mowing (58% of present counts) or soil movement (22 %). Roads and their associated right-of-ways are acting as dispersal corridors and providing a maximized habitat in which cogongrass is able to thrive. Well-established forest interiors (buffered by an edge of dense vegetation) are relatively free from invasion unless there has been an anthropogenic dispersal vector created into the area (i.e., logging road, H20 drainage cuts into forest).