This reduces species diversity, alters natural ecosystems, and negatively impacts wildlife habitat. To see just how fast Japanese Knotweed spreads, here is a time-lapse video of Japanese Knotweed growth. But there are no male knotweed plants in the UK, which begs the question – how does Japanese Knotweed Gloucestershire located and elsewhere spread and multiply? It is often quoted that a fragment weighing just 0.7g can produce a new plant. Japanese knotweed spreads by disturbance and spreading of the root system that stimulates re-growth. They have always been highly reliable, flexible, and completely professional. The ground under knotweed thickets tends to have very little other growth. While these plants can grow and exploit a range of site conditions, they seem most comfortable along riverbanks and roadsides here … It is not native to the British Isles and as such it is not exposed to any of the controlling organisms that maintain it to its natural extent in its countries of origin (i.e. Rhizomes allow knotweed to spread quickly and aggressively and new colonies can form from very small stem or rhizome fragments. Japanese Knotweed is native to Eastern Asia, including Japan, China and Korea. Japanese knotweed spreads via the transferral of contaminated soil, or the unlawful tipping of cuttings. The mere presence of Japanese knotweed in or even near domestic gardens is making it problematic to get a mortgage, and therefore buy and sell property. Prevent spread of Japanese knotweed. As the plant’s root systems can spread … In order to understand this, we require a quick plant physiology lesson. It grows to heights of , and the roots can be twice that deep. What’s more, disposing of it can be very difficult. Japanese knotweed can easily be spread by transferring from shoes or clothes, this can happen when people walk through a contaminated area. It is spread by people, machinery and water. The reason for this is that only female plants were imported, which means any seed produced are sterile. The problem with Japanese Knotweed is that it can sprout from as little as 2mm of rhizome, meaning it is classed as “controlled waste” under the Environmental Protection Act of 1990 and must only be disposed of into licensed landfill sites to stop further spread. Jumbo planters for your garden: How to choose? However, knotweed is a dioecious plant, meaning both flowering females and fertilising males are required to produce viable seeds. We have used Phlorum on many jobs to eradicate Japanese knotweed successfully. Less than a gram of knotweed root is required to produce a new plant. Japanese knotweed’s ease of spread and rapid growth from a deep rhizome (root) system was initially prized for planting schemes. You will be liable for the spread of the plant even if you have attempted to stop its spread by composting or burying it. This means that Japanese knotweed can easily be spread via the transport of top soil from affected areas. Once it begins to flourish, it can quickly ravage stone and brickwork within the course of a year. In its native home seed dispersal is one of the ways it spreads, but in the UK, it is only on very rare occasions that it spreads this way. The popular press has picked up on a landmark legal ruling in which Phlorum recently provided expert witness services. The 2018 study also found that Japanese knotweed rhizomes rarely extend more than 4m from the visible plants, and usually spread less than 2.5m. However hybridisation, the process whereby a plant is able to breed with an individual of another species, is possible with Japanese knotweed. Japanese Knotweed can grow up to ten cm per day, with roots growing out in a seven-metre radius, meaning it can quickly spread from one garden to another, infesting whole areas. In winter the plant dies back to ground level but by early summer the bamboo-like stems emerge from rhizomes deep underground to shoot to over 2.1m (7ft), suppressing all other plant growth. … Eight Easy Ways to Combat Invasive Plants You can help stop the spread of invasive plants by following these 8 easy guidelines: 1. Follow this link for guidance on Japanese knotweed identification. We will continue to use Phlorum on future projects and I would recommend them to others. Japanese knotweed, or Fallopia Japonica, was brought to Europe from Japan in the mid-19C by German-born botanist Phillipp von Siebold who found it growing on the sides of volcanoes. 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