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A stand of Japanese knotweed
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A large mature stand of Japanese knotweed
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Japanese knotweed leaves are shield-shaped and grow alternately on the stem
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Japanese knotweed stems are green, speckled with pink/purple and segmented like bamboo
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An indication of scale of mature Japanese knotweed stems
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A cross-section through a hollow knotweed stem
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A Japanese knotweed crown
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Red emerging buds from crown material at the base of mature knotweed stems
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A stand of Japanese knotweed in flower
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Japanese knotweed flowers
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A section of mature Japanese knotweed rhizome
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A cross-section of Japanese knotweed rhizome showing the bright orange colouring
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The internal orange colouring makes live knotweed rhizome easy to spot when disturbed
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An excavation reveals two sections of Japanese knotweed rhizome
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Crowns from a large Japanese knotweed stand showing strong but distorted (‘bonsai’) regrowth
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Stunted ‘bonsai’ regrowth of a Japanese knotweed plant
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A more extreme form of knotweed ‘bonsai’ regrowth
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A mature Japanese knotweed stand during the winter months, showing upright dead stems
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Winter brushcut operations on a large Japanese knotweed stand
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Giant knotweed
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Hybrid (‘bohemica’) knotweed – note significant variation in leaf shape
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Himalayan knotweed
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Dwarf Japanese knotweed
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Leaf size and shape comparison of different knotweeds in the UK
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Mature emerging Japanese knotweed stems
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Fully grown mature knotweed stand
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An uncontrolled Japanese knotweed infestation on a neighbouring property
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The inevitable result when mature knotweed is paved over without prior remediation of the knotweed
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Mature knotweed has historically been concreted over but continues to emerge around the edges and through cracks
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Japanese knotweed emerging through decaying tarmac
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Japanese knotweed has found a weakness in a decaying wall and has grown inside a property
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A large Japanese knotweed rhizome discovered within a section of drain pipe
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Japanese knotweed growing through a poorly-maintained wall
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A knotweed crown has grown at the meeting point of two walls and exerted so much pressure over time it has cracked the wall
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Knotweed was allowed to grow for many years in a narrow gap between a building and a wall, resulting in the eventual collapse of the weaker structure
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Japanese knotweed will not typically create ingress into a building, but it will take advantage of any access points that are created by other means
