Identify Japanese Knotweed in Winter

Japanese Knotweed | 15th March 2016

Identify Japanese Knotweed in Winter

You might be forgiven for thinking that identifying Japanese knotweed in winter would be simple. However, despite Japanese knotweed having developed its capabilities growing high up the slopes of active volcanoes, Japanese knotweed in winter likes to shelter away from the cold and damp, the frost and snow, hiding away underground where it’s large rhizome system (roots) holds on to all the energy it squirreled away during the summer months. In late autumn, Japanese knotweed leaves start to fall just like those of deciduous trees, leaving bare canes behind by the winter.

Identifying Japanese Knotweed in Winter

The above-ground signs can be hard to spot, especially if the infestation is small, where the stems are easily broken and flattened. Japanese knotweed winter growth can take place when the weather remains mild and the area is sheltered but this is quite rare (luckily!). Larger stands, however, can be very obvious and quite impressive, with hordes of Japanese knotweed winter canes standing resolutely against the wind and rain.

However, winter Japanese knotweed stands in urban settings are rarely glamorous – picture a combination of dropped and decaying leaves plus wind-blown and fly-tipped rubbish clustered around and among the knotweed canes – nice. Rural infestations of Japanese knotweed might contain less waste but can be an environmental disaster, wrecking local ecosystems and causing erosion along riverbanks. Winter floods can even help Japanese knotweed to spread further, as fragments of knotweed rhizome get transported downstream to new locations.

How To Identify Japanese Knotweed Appropriately

Perhaps the best method of Japanese knotweed identification in winter is the up-close approach. Examination will highlight the stems which zigzag as they grow skywards, the brittle and hollow brown canes which look a bit like dark bamboo canes and the crumbly remains of the flower clusters. If you are getting physical in your attempts to identify Japanese knotweed in the UK, please ensure that you are not guilty of spreading the plant. Make sure you kick off any mud and vegetation from your boots before moving on and check your clothes for any knotweed fragments, leaving anything you find where it came from.

Possibly the best way of identifying Japanese knotweed in winter is to simply ask the people in the know – Call PBA Solutions now on 0203 174 2187 for advice and an on-site knotweed survey.


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