When Invasive Species have Benefits as well as Costs: Managing Carex kobomugi (Asiatic sand sedge) in New Jersey’s Coastal Dunes

Abstract

Asiatic sand sedge, Carex kobomugi, was accidentally introduced into North America approximately a century ago and is now widespread along the Northeast coast of the USA. This paper documents the rapid spread rate of this species in two New Jersey coastal parks. Also documented are declines in native plant densities, species richness and diversity in invaded areas. Although C. kobomugi expansion is having negative ecological impacts, the species is a potentially important dune stabilizer, so its control or removal demands special care. A removal program was initiated in 1999, using carefully directed applications of Roundup Ò , which was designed such that it would spare non-target plants, leaving them in place to hold the dunes. We show that this approach reduced, but did not eliminate, C. kobomugi, even after repeated herbicide application. Native plant stem densities, species richness and species diversity in treated and untreated stands were similar, suggesting that this application technique did effectively spare non-target plants. However, effective eradication of C. kobomugi would probably require more frequent and aggressive broadband herbicide application, precluding beneficial effects of localized treatment (both ecological and increased dune stability due to spared plants).

Effectiveness of methods to control the invasive non-native pitcherplant Sarracenia purpurea L. on a European mire

“…Matarczyk, Willis, Vranjic, & Ash, 2002;Wootton et al, 2005;MacDonald, Scull, & Abella, 2007;Kettenring & Reinhardt Adams, 2011). This usually occurs when the herbicide comes into contact with neighbouring plants, either as drips or drift, and this can occur even when it is applied very locally with a spray (as in this study), wick, wiper or roller.…”

A species effect on storm erosion: Invasive sedge stabilized dunes more than native grass during Hurricane Sandy

“…This highly clonal species reduces native diversity and out‐competes the once dominant, also clonal, American beachgrass ( Ammophila breviligulata ; hereafter AB; Wootton et al . ). Both species are effective dune stabilizers, but may build different dune morphologies (Lea & McLaughlin ; Wootton et al .…”

Methods of Suppressing Colonizing Sedge to Help to Establish Tree Seedlings in a Natural Forest

“…In a similar case of herbicide application to sedge in a natural field, it has been reported that Carex kobomugi, an invasive foreign species in coastal dunes, was reduced but not eliminated after repeated herbicide (Roundup) application [11]. In comparison, Carex oxyandra was suppressed for approximately two years by herbicide treatment, so careful choice of herbicide and examination of its effectiveness are needed according to the target plant species.…”