Scary plant story

Discussion in 'Plants: In the News' started by Lysichiton, Oct 27, 2011.

  1. Lysichiton

    Lysichiton Active Member

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    Japanese Knotweed is definitely not funny nor a Halloween prank. This story is from the UK where Fallopia japonica has a whole section of the building code all to itself:

    http://www.dailymail.co.uk/news/art...home-rid-Japanese-knotweed.html#ixzz1c1sUAXA5

    This plant is in an explosive phase of spread around the Lower Mainland right now. I am waiting for people to wake up to the threat it poses, greater than that of any other higher plant invasive we have right now, IMO.
     
  2. Barbara Lloyd

    Barbara Lloyd Well-Known Member

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    Are both the Japanese Knotweed (P. cuspidatum) and the Giant Knotweed (P. sachalinense) equally invasive? From what I read it appears as tho they are. What is the best method of killing this stuff?
    barb
     
  3. Lysichiton

    Lysichiton Active Member

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    What I call slash & drip has worked well for me. Knotweed stems are hollow. Cut the stems so there is a hollow section left attached & then drip about 5-10ml of undiluted glyphosate in the hollow stem. If you do this to most or all of the stems in the stand, you will kill it. I use a large syringe without a needle, scrounged from a local health professional, to neatly put the stuff in the little tubes without getting it all over the place.

    This is not an approved use of pesticide where I live, I don't think, so I have only done this on my property or that of my family. Check your local regulations.

    Don't just cut the tops & think you are doing any good. In my experience it will break into dozens of new shoots & sucker over long distances.
     
  4. woodschmoe

    woodschmoe Active Member 10 Years

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    That's a very scary story, for sure, but the first of it's kind I've ever heard. So, it's not as though houses everywhere are in imminent risk...it likes to spread, for sure. Yet it's been around the Lower Mainland for at least 50 years (in the UK since the Victorian era), doubtless longer (I used to play in groves of it as a kid...groves, it should be noted, that bordered homes on each side), and I've not heard any local stories like this. Certainly the houses by my old stomping grounds are still standing and leafless. So why so few such stories like this (in fact, only this one, it would appear)?

    There's more to this story, I'd wager, details particular to the site and/or the house, or the lax owners. A survey of this yields very few other examples of serious damage to a house. One site (a UK firm dedicated to its' eradication) admits that the damage is often 'overstated'...they themselves can only cite a single example of it growing into a cavity wall: I've seen a lot of native stuff growing through old walls and foundations too (I'm constantly pulling the canes of the 'native' Rubus leucodermis out from under the siding of my house).They have an interest, as a business, in citing every example they can find. It's the root of their success. And yet they can only cite one. They do warn however that it will...gasp...cause 'fences to lean'. A sure sign of the coming apocalypse.

    It's apparent that there is a current hysteria in Britain around the stuff, and insurance companies are using its' presence to deny coverage. Their risk metrics are rather strange, though, and often reflect a rather different reality. The comments under these stories are the real story: in one, a structural engineer who deals with the stuff in the course of their work points out that if the house is in sound condition, it's not an issue. This would seem to be supported by the above mentioned fact that it's been around for quite a while, and stories like this aren't exactly legion. What we have is hysteria based not on a notorious house eating plant, but instead based on the uber-cautious policies of insurance providers. And to an insurer, everything from ornamental ponds to skateboards are ticking time bombs.

    I doubt it's in an 'explosive phase of growth'...like I said, it's been here for a long time; why would it suddenly 'explode' in a regional sense? Perhaps due to a changing climate, but far more likely that our anxiety around it has exploded, hence we pay more notice to it, hence we see more of it....none of this, of course, is intended to dispute its' unneighbourly ways, but I think the hysteria is, well, hysterical. Control it if you wish. In some cases you'll indubitably be working on behalf of other plants and assemblies it's supressing; in others, you'll simply be keeping the gravel road shoulder or the barren lot pristine. Doubt you'll be saving the architectural legacy of western civilization, however...though if it could be engineered to only attack vinyl homes, I'd join team knotweed.
     
    Last edited: Oct 28, 2011
  5. Lysichiton

    Lysichiton Active Member

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    Centre for Invasive Plant Management :

    http://www.weedcenter.org/textbook/3_rados_invasion.html

    F.japonica is currently in colonization phase with a geometric increase in spread in Lower Mainland....my possibly overly-dramatic attempt to popularize the description is "explosive".
     
  6. woodschmoe

    woodschmoe Active Member 10 Years

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    Ahh...gotcha. Boned up on lag-time. Skepticism somewhat tempered (on that point). Due, it would seem, to an exponential increase in disturbance, perhaps a consequence of construction booms in recent decades. So perhaps an 'explosion' after all. Still worth considering if the negative effects of knotweed colonization are worse than the far greater and more total destruction created by the initial disturbance, of which the knotweed is merely a symptom. I'd extend the ecological process at the tail end, however and suggest what the cited study appears to leave out (I might have missed it): outbreaks ('explosions') are typically followed by 'crashes', and knotweed will become a permanent (and eventually diminished) part of the constantly evolving palette of what eventually come to be called 'native plants'. In a changing climate, might be more sensible to push for select removal rather than total eradication....invasions have occurred throughout pre-history, after all, and today's native was yesterday's alien. Red Cedar (insert 'not actually a cedar' here) once invaded from the south, and it's none too kind to other plants. Imagine if the Salish had pulled 'em. Still, I doubt the knotweed is going to foster a coastal renaissance any time soon, unless we as a society turn to the mass production of cheap flutes. So perhaps it's not worthy of such a vigorous defense.
     
  7. maf

    maf Generous Contributor Maple Society 10 Years

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    This case was even featured on TV in England last week. They lifted the floorboards for the cameras and showed the knotweed running along the spaces underneath.

    In the UK the professionals add a dye to the herbicide they are injecting into the stem so they can easily see which stems they have treated and, more importantly, to make sure they do not miss any. It will take repeated treatments over several years before a site is given the all-clear.
     
  8. Michael F

    Michael F Paragon of Plants Forums Moderator 10 Years

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    Japanese Knotweed a serious problem in some places, but nothing like as bad as that Daily Mail article makes out. That's all just bad sensationalist journalism, absolutely typical of the gutter press like the Daily Mail.

    Actually, the Daily Mail is not so much gutter press any more, it's gone down into the sewers.
     
  9. Lysichiton

    Lysichiton Active Member

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    I am sure that is true about the gutter-press in the UK. I read some of the newspapers with amazement & disbelief when I visit the UK.

    However...Down the road here this plant is ineradicably invading the main railroad line, lifting up the tarmac in an adjacent parking lot & moving concrete barriers about to suit it's own ends. That's just one of many infestations locally.

    Sorry, but this plant alarms me. I strike first & hard when it is anywhere on or near my properties or those of my family.

    BTW, how is the biological control going in the UK? Any early indication if it might work?
     
  10. Michael F

    Michael F Paragon of Plants Forums Moderator 10 Years

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    Too early to say. Trial releases only started last year, and I've not seen any results published yet.
     

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