Monday, July 11, 2011
To pull or not to pull?
As part of my research project this summer at VINS I have been charged with investigating invasive species ecology – how these species interact with the ecosystem they have invaded, as well as management strategies to minimize their impacts through eradication.
Exotic invasive species are managed because of the threat they pose to native flora and fauna by physically displacing native species. However this is not the only way invasives do harm to local ecosystems. Some exotics like the stump-sprouting Japanese Knotweed pictured above, have the ability to alter the actual physical and chemical composition of soil. Doing so disrupts the hydrology, nutrient cycling, soil microbial and fungi populations which all exacerbates the problems posed by invasives.
As the above picture illustrates, managing invasive species is not always effective, in-fact, managing an invasive species population never really ends. Seed dispersal of a plethora of invasives, whether it be by wind, bird, animal or human is inevitable. So it seems the same question must be asked, “To pull or not to pull?” Concentrating management efforts to the most sensitive areas seems the most economical, but if invasives cannot be managed everywhere are our actions fruitless? When exotic ornamental Japanese Barberry still holds a multi-million dollar market share in the horticulture business (Lehrer et al, 2006) it would seem our attitude towards acceptable landscaping practices needs to make a change before real progress towards managing invasive populations can take place.
Lehrer, J et al. (2006). Four Cultivars of Japanese Barberry Demonstrate Differential Reproductive Potential under Landscape Conditions. Journal of Horticultural Science. Vol. 41 Iss. 3 (pp762).