Over the course of this blog I've covered invasive species problems from all over the world. Now I have come across a case much closer to home. Within a few miles, in fact, of the place I call my own, Hemel Hempstead, in South East England.
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| It gets called plenty, but I call it home... |
Famous for
giant oil explosions and recently being
voted the UK's ugliest town, the latest travail it is encountering is the
invasion of Japanese Knotweed on the rather nice
Nickey Line pathway.
Japanese knotweed is native to Japan, Korea and China and was introduced to Britain in the 1850s
(Bailey and Conolly, 2000). It is regarded as the most pernicious invasive weed in the British Isles
(Mabey, 1996) and since 1981 it has been a criminal offence to introduce Japanese Knotweed
(Hollingsworth and Bailey, 2000).Despite this, halting it's spread has proved impossible.
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| Distribution of Japanese Knotweed, then and now. Source: Cabi.org |
It is an aggressive invader that causes substantial economic and environmental damage in the UK
(Smith et al., 2007). Amongst these include impacts on native flora, increased flood risk, physical damage to buildings (its roots can grow through concrete) and it can obstruct public access to certain areas (ibid). The plant is problematic to remove as it spreads from its rhizomes rather than seeds (
Environment Agency, 2013).
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| No place for a plant: Japanese Knotweed growing through a wall. |
Luckily the local council is taking the required action in the very near future. Drains are to be replaced and improved, new tarmac will be layed on the path and the plants will be treated and removed.
In an attempt to ensure the hardy plant doesn't continue to grow or return, a large area around the plant will be excavated to a depth of about 3 metres. The dug up earth will be sent to a special landfill and a copper shield is to be inserted before the area is restored.
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| A site of Japanese Knotweed removal in nearby Watford, looks...rooty...? |
If you happen to spot any possibly harmful plants in the Dacorum Council area, you can call the trees and woodlands department of the local council on 01442 228000.
Over and out
The Invader Inspector
Hi Rob!
ReplyDeleteCool that you've managed to relate invasive species to something so close to home! Have you got any of your own pictures?
I am going to throw a limb out there and assume that Japanese Knotweed isn't only found in Hemel. Where else would you find it? Is there a black market for it in Britain seeing as it's illegal? Not sure why you would want it though!
Over and Out Inspector!
Isabela Depedro
Hello Isabela Depedro
DeleteYeah I know! I have to give credit to my dad for that, he's the one that keeps up with the local news! I don't have any of my own pictures, the weather has been a bit horrible and there was one in the article so I thought that would do ;-)
Your limb would be safely thrown. The plant is also invasive in much of western Europe and also nearly all of the eastern states of America.
I don't know if there's a black market for it, and I'm a bit scared to try and find out if there is one what with nothing being private anymore... but seriously, I highly doubt it. Back in the day it was popular in gardens because people saw it as 'exotic' (think we covered that sort of stuff in Self-Other, Ideas in Geog, 1st year, ugh) but nowadays i'm sure people wouldn't seek it out. As a plant it doesn't look particularly impressive, and as we've seen, it can cause rather a lot of damage.
Hope that answered your question! :-)