A new paper discusses biological control (using natural enemies) of plants that have escaped from gardens and are invading wild habitats in UK. These include Japanese knotweed, Himalayan balsam, Australian swamp stonecrop, floating pennywort, giant hogweed, water fern, rhododendron and buddleja.
Himalayan balsam (Impatiens glandulifera) promotes soil erosion along watercourses, according to research published in the Journal of Soil Sediments last month (Dec 2013)
Philip Greenwood and Nikolaus Kuhn from the University of Basel show that erosion along riparian zones is statistically greater where Himalayan balsam is present when compared to topographically comparable sites that support natural vegetation.
Volunteers from RINSE (Reducing the Impact of Non-Native Species in Europe) performed a survey of the River Bure (in the Norfolk Broads), tracking it from source to sea and seeing how many invasive plants such as Himalayan balsam they cam across.
See their website for more information and a map of their results.
Himalayan balsam is one of the UK’s most widespread invasive weed species, colonising river banks, waste land, damp woodlands, roadways and railways. Research by CABI scientists has shown local invertebrate biodiversity is negatively affected by the presence of Himalayan balsam. This leads to fragmented, destabilised ecosystems, which has serious consequences on processes and functioning, and complicates habitat restoration unless remedial actions are implemented.
Tanner, R.A., Varia, S., Eschen, R., Wood, S., Murphy, S.T. and Gange, A.C. (2013) Impacts of an invasive non-native annual weed, Impatiens glandulifera, on above- and below-ground invertebrate communities in the United Kingdom. PLoS ONE 8(6), e67271, 13pp. doi:10.1371/journal.pone.0067271