Optimising physiochemical control of invasive Japanese knotweed
Fallopia japonica var. japonica (Polygonaceae: EPPO List of Invasive Alien Plants) can have significant impacts on biodiversity and ecosystem services and cause landowners considerable costs in management and eradication programmes. In a three-year experiment carried out at three sites in south Wales (United Kingdom), fifty-eight 225 m2 treatment and control plots were established and 19 control methods were tested for effectiveness. The methods included the application of different chemical controls at varying application rates and timings, and physical control treatment comprising of covering F. japonica var. japonica with high density polyethylene and hand pulling any emerging growth from around the covering. Although none of the methods tested eradicated F. japonica var. japonica, a several applications of glyphosate treatment yielded the greatest control. The authors of the research suggest: when designing management strategies, effective control of F. japonica may be achieved by biannual (summer and autumn) foliar glyphosate applications at 2.16 kg AE ha−1, or by annual application of glyphosate in autumn using stem injection at 65.00 kg AE ha−1 or foliar spray at 3.60 kg AE ha−1.
Sources
Jones D, Bruce G, Fowler MS, Law-Cooper R, Graham I, Abel A, Street-Perrott FA, Eastwood D (2018) Optimising physiochemical control of invasive Japanese knotweed. Biological Invasions. https://doi.org/10.1007/s10530-018-1684-5