Japanese Knotweed Identification – A Complete Guide. Japanese knotweed Japanese knotweed (Fallopia japonica), is an invasive herbaceous perennial (a plant that can live more than one year). It invades a wide variety of habitats and forms dense stands that crowd out other plants. Thread starter S2Klay; Start date Apr 21, 2020; S. S2Klay LawnSite Member. Nationwide Services for Ireland & UK. Hipkins, P.L. Sci. Managing Japanese Knotweed Japanese knotweed (Polygonum cuspidatum) is an imposing herbaceous perennial that is commonly called 'bamboo'. Stems are round, smooth and hollow with reddish-brown blotches. This perennial herb grows up to 10 feet tall, with heart-shaped leaves and white flowers. Different solutions for removing Japanese Knotweed include herbicide treatment, stem injection, excavating infected areas of ground with machinery, or a Japanese Knotweed root barrier to halt the spread of the irksome weed. Our experts will advise on the best course of action when they visit your site. The Problem. Application method Timing Aquatic approvedNotes Info source aminopyralid Milestone (40.6%) Manufacturer recommends 6-14oz/acre for Japanese knotweed. Proc. Foliar Spray. If you are planning to build on, landscape or otherwise disturb the area, it is better to have the Japanese Knotweed excavated. Unknowing Victorian botanists brought the weed over to the UK because they liked its aesthetic appeal, its similarity to bamboo and the fact that the stems could grow large enough to be used as fences. River Urr & River Dee, Stem Injection of Japanese Knotweed, Galloway Fisheries Trust. Look up the regulations concerning Japanese knotweed in your area. and H. Witt, 2004. Timescale: 3-5 Growing Seasons Using a knapsack sprayer, herbicides are applied to the top and underside of the plants leaves surface. • This reliance on herbicide has lead us to look for an alternative… • Surface growth from previous seasons is cut and cleared • Mesh is laid across the surface growth and rhizome area • Japanese Knotweed stems emerge from buds on the underground rhizome crowns in April Mesh Tech Control Technique: Japanese knotweed stems emerge through the 13mm galvanised steel mesh. The Solution. For more information on these exceptions and applicable procedures, please refer to the Ontario Invasive Plant Council’s Best Management Practices document for Japanese knotweed. Management of Japanese knotweed Herbicide Application. Location Pittsburgh, PA, USA. Infamous for its devastating ability to cause costly damage to property, Japanese knotweed is the most widespread form of knotweed in the UK. and H. Witt, 2005. Plant Control: Apply a glyphosate herbicide in combination with cutting. Japanese Knotweed Herbicide Treatment Options (Mid-Michigan Stewardship Initiative and Northern Michigan Invasive Species Network) Chemical name Brand name (% active ingredient in this brand)Rate Surfactant/ adjuvant needed? It is very difficult to remove large or well-established infestations without the assistance of herbicides. Stem injection was used to eradicate a stand of Japanese knotweed in the front garden of a house in St Andrews. Southampton. Overview Other names for this plant include: Common names: Japanese bamboo, Mexican bamboo, fleece flower; Scientific names: … Japanese knotweed: a particular case in point In the UK, there are four invasive knotweed species, collec-tively referred to as Japanese knotweed sensu lato (s.l. Encroachment of Japanese knotweed on to neighbouring property may give rise to a liability under a private nuisance claim. Further, where individuals are acting unreasonably and persistently in a way that has a detrimental effect on the quality of life of those in that locality, for example by allowing the unmanaged growth of knotweed, local Knotweed spreads vegetatively by rhizomes and also sprouts from fragments of root and stem material, which are dispersed by water, equipment or in fill. By Paolo Martini on 2nd July 2019 (updated: 9th December 2020) in News. While you could always use a glyphosate herbicide such as Roundup, this can be harmful to the environment. Timing is everything. There are several herbicide products on the market that can be used to combat Japanese knotweed and they have varying degrees of effectiveness, as well as differing impacts upon the surrounding land and vegetation. Typically blooming between late summer and early autumn, Japanese knotweed flowers are a distinct creamy white colour and … Department of Plant Pathology and Weed Science, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, VA. Hipkins, P.L. With Japanese Knotweed and other invasive plants inhabiting a vast number of development sites in the UK, and our reputation for excellent and effective treatment, we are sure we will continue to grow. This happens twice a year; once during the early part of the growing season (April – June) and then again during late summer/autumn (July – September). Killing Japanese knotweed regrowth following treatment with glyphosate-based herbicides the environment, reduces biodiversity and degrades quality... Form of knotweed in your area, Bunds, Soil screening & On/Off site dig Dump! Mine spoil to shaded streambanks riparian habitats by Paolo Martini on 2nd July 2019 ( updated: Subscribe. 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