Management of Elodea nuttallii in Ireland
Elodea nuttallii (Hydrocharitaceae: EPPO List of Invasive Alien Plants) is an aquatic plant species native to North America. E. nuttallii probably arrived in the EPPO region in the 1970s and became invasive in 2000, and the invasion is still ongoing. In Ireland, E. nuttallii was first reported in 1984 and occurred almost exclusively in lakes until 2000, but in the subsequent decade it was most frequently recorded in canals and rivers. In Ireland, E. nuttallii poses a significant threat to Natura 2000 sites. Elodea nuttallii has been successfully controlled in other regions of the world using jute matting. This is an environmentally friendly, biodegradable geotextile, which acts as a benthic barrier that excludes light inhibiting plant growth. In addition to controlling invasive macrophytes, this geotextile has been shown to permit the regeneration of charophytes in areas where treatment occurs as they can grow through the small apertures in this benthic barrier. A trial was carried out in Lough Arrow Lake in the north-west of Ireland where E. nuttallii, is a relatively recent arrival. Two experimental areas covering a total of 800 m2 were treated by covering E. nuttallii with jute textile. A single layer and double layer of jute textile were trialled. respectively. The trials were successful in controlling E. nuttallii with either a single or double layer. For each treatment, the percentage cover of E. nuttallii was reduced by 60%. In addition, the percentage cover of the indigenous charophyte flora was unaffected by the jute textile.
Sources
Garland D, Earle W, Caffrey J, Taylor C, Meehan S, Touzet N, Lucy F (2022) Management of the invasive Nuttall’s pondweed (Elodea nuttallii) in Lough Arrow, a Natura 2000 designated lake in Western Ireland. Management of Biological Invasions 13(1), 118–130. https://doi.org/10.3391/mbi.2022.13.1.07