Author
Rinella, Matthew - Matt | |
MAXWELL, BRUCE - MONTANA STATE UNIVERSITY | |
Sheley, Roger |
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 12/1/2007 Publication Date: 1/26/2008 Citation: Rinella, M.J., Maxwell, B.D., Sheley, R.L. 2008. One-Time Herbicide use Causes Local Extinction of Native Species. Society for Range Management Meeting Abstracts. 23-10. Interpretive Summary: Invasive species are depleting native species. When ecosystems become invaded, ecosystem managers face a difficult dilemma. They can use aggressive practices to reduce invader abundances, thereby reducing invaders’ competitive impacts on native species. But it is usually difficult or impossible to reduce invaders without damaging native species to some extent. If, when, and where this collateral damage to natives will be offset by positive effects of reduced invader competition is a major unknown in invasive species management. We studied several rangeland natives that had been coexisting with an invader leafy spurge for several decades. We asked if damaging invasive species management (herbicide use) altered this picture of long-term coexistence. Our 17-year study showed one-time herbicide use permanently rarified some natives, drove some natives locally extinct when cattle-grazing was excluded, and likely increased invader abundances over time. Herbicide applications are doubtless warranted in some situations, but there are also circumstances where herbicide use is ill-advised. Technical Abstract: Invasive species are depleting the World’s native biota. When ecosystems become invaded, ecosystem managers face a difficult dilemma. They can use aggressive practices to reduce invader abundances, thereby reducing invaders’ competitive impacts on native species. But it is usually difficult or impossible to reduce invaders without collaterally damaging native species to some extent. If, when, and where this collateral damage to natives will be offset by positive effects of reduced invader competition is a major unknown in invasive species management. We studied several rangeland natives that had been coexisting with an invader (leafy spurge (Euphorbia esula)) for several decades. We asked if collaterally damaging invasive species management (herbicide use) altered this picture of long-term coexistence. Our 17-year study showed one-time herbicide use quasi-permanently rarified some natives, drove some natives locally extinct when cattle-grazing was excluded, and likely increased invader abundances over time. Herbicide applications are doubtless warranted in some situations, but there are also circumstances where herbicide use is ill-advised. |