Does any one know how to get rid of this demonic plant, it’s slowly taking over a local waterway, most of the literature I read said glysophate helps, but that’s toxic to water life. Any suggestions?

  • supersquirrel@sopuli.xyz
    2·
    3 months ago

    Are you in north america? Yeah, it is a brutal invasive here probably one of the most difficult to get rid of I have encountererd.

    You need specialized help and you need to do it all together at once to make sure it doesn’t come back, it is not something to mess around with.

    Honestly the best way to get rid of it I have seen is to cut it down at the right time and then place a tarp over it and just starve that area of ground of sunlight for long enough to kill it…

    • Thebigguy@lemmy.mlOPEnglish
      3·
      3 months ago

      No I’m in Europe, I’ve been reading academic literature and from what I’ve read there is no real good way to get rid of it. It’s also on public land can you just use any standard black tarp?

      • supersquirrel@sopuli.xyz
        1·
        3 months ago

        I am not sure it is really possible without glysophate unfortunately. It is simply too aggressive of an invasive plant and the root system can go very very deep and far laterally.

        https://www.reddit.com/r/NativePlantGardening/comments/woywrl/knotweed_eradicationreplacement/

        As much as I have seen it over the landscapes of Southern New England and the Pacific Northwest in the US, I have never talked to someone that successfully removed it without pesticide, I don’t know, I am sure there is a way but I don’t know of it and I think a lot of people would be interested if you came up with an effective way to do it…

        …I have literally heard of property values in the US being depressed by the presence of japanese knotweed because it is so difficult to eliminate…

        Whatever you do, make sure your local community understands japanese knotweed isn’t one of those cute invasive plants that just requires the community to come together to pull it up and eradicate it together in a big push… no you let it get out of control that is it. There is nothing cute about the way the plant interacts with north american northern forested landscapes, this ain’t morning glory or some other mundane invasive.

        I imagine that in Europe the way japanese knotweed tends to slot in to the ecosystem might be different but I don’t think it would be tooooo different from how out of control japanese knotweed acts in the ecosystems here. Every species must be considered in an ecosystem as context, but the climate of a lot of Europe is very well situated to japanese knotweed similar to New England in the US and the PNW.

        Edit someone mentioned this in a reddit thread about getting rid of japanese knotweed, not sure if it is legit or not but I think thorough meaningful removal of japanese knotweed is going to take a unique approach like this if you don’t (understandably) want to resort to nasty chemicals.

        https://naturavolt.com/

        • Thebigguy@lemmy.mlOPEnglish
          3·
          3 months ago

          Glysophate is toxic to aquatic organisms so I don’t think that would come in question. From all the literature I’ve read it seems like the other option is covering it, this would be expensive though and I’m broke and all of this is growing on public land and you have to cover it for up to six years. Another method I read about is a guy making a grid out of metal and placing that where the knotweed grows and the stems are cut as they grow thicker than the grid. I was just wondering if any one here has any experience with it.

          This is along the banks of another river that’s downstream. Knotweed and one other plant as far as you can see. This plant is just as invasive and dangerous here as it is in NA

          • supersquirrel@sopuli.xyz
            1·
            3 months ago

            Fair enough, I wasn’t trying to be forceful about recommending pesticides, I sure as heck don’t feel comfortable doing that I was just trying to relay what I know about the effectiveness of different methods.

            One useful perspective that this paper proposes is instead of trying to eradicate it with a nuclear pesticide removal option, treat it as a crop to be harvested and turned into things humans want.

            https://pmc.ncbi.nlm.nih.gov/articles/PMC8705504/

            Of course this is a bit of an idealistic perspective, but one actionable item I think that would be possible is raising awareness that japanese knotweed is both a problematically prolific invasive and also as a potential raw material to make valuable things out of or at least create lucrative amounts of honey off of with nearby hives. Then one could envision a public policy where harvesting of japanese knotweed from public lands was allowed along certain conditions (depending of course on local laws and the local political realities).

            I mean… even if it remains illegal to remove japanese knotweed or harvest in huge amounts that reduce its population significantly in an area… there is definitely an argument that who is going to stop you if you do it in a way that benefits everybody? Yeah someone eventually will… but idk. Just a thought.

            • Thebigguy@lemmy.mlOPEnglish
              1·
              3 months ago

              I want to try the shoots next spring and see what they taste like, from what I’ve seen it’s so aggressive that keeping it in check somehow is probably the best solution. I saw there are some insects you can use, but I’m kinda interested in the electric method. I just started reading about this like two days ago.

              https://oa.mg/work/10.5424/sjar/2020181-15542 Apparently you can also use it as a foliar spray and it helps against slugs. I’m pretty bad at reading scientific papers though.

        • Thebigguy@lemmy.mlOPEnglish
          2·
          3 months ago

          I was reading about electrical weed management from the literature I gathered that I would need to run a current through the plant that’s higher than the plants internal resistance, I was wondering how I could go about reading the resistance of the knotweed? Any ideas?

          • supersquirrel@sopuli.xyz
            1·
            3 months ago

            There isn’t going to be a defined eletrical resistance you can tune to in general, I think it is going to largely depend on the situation… how much water is in the plants when you do it, how old the plants are, how intertwined roots are… what kind of soil it is etc… However, any method you would use to apply the electrical current to the Japanese Knotweed would also be almost if not the same kind of setup you could measure the resistance of the Japanese Knotweed with correct?

            The idea of sensing the electrical resistance of a Japanese Knotweed plant is really just the same very well established idea used all the time in geology called an Electrical Resistance Survey

            https://en.m.wikipedia.org/wiki/Electrical_resistance_survey

            Four electrode measurement

            In a four electrode measurement we apply a direct current voltage across two electrodes (known as the current electrodes). This creates a current and an associated potential field in the subsurface. We can now measure both the current between the current electrodes and the electrical potential across two other electrodes (the potential electrodes). From the current (in Amperes) and potential (in Volts) we can calculate a so called transfer resistance with Ohm’s law (R=V/I). This transfer resistance is a function of the electrical properties of the subsurface and the electrode geometry.

            https://subsurfaceinsights.com/electrical-resistivity-method/

            Essentially what I am suggesting is to jam to spikes into a japanese knotweed plant, drive a large current through it and measure the resistance as you would with a multimeter in a sense. In geophysics terms you are looking to measure how much resistance the ground has to the electrical current being induced through it, I imagine it is a reasonable hypothesis that a similar method can be applied to a dense network of near surface rootsystems of japanese knotweed and soil at a much smaller scale.

            https://kerstenuk.com/blog/Chemical Free Weed Control/using-electricity-to-kill-japanese-knotweed

            The Principle -

            The system is based on electrophysical technology. The device generates a very high current pulse at the touch of a button, thereby eliminating unwanted plants in a targeted manner. The power module supplies the high voltage required for this, this current flows via the hand lance into the plant and then into the substrate. The circuit is closed again via the current feedback earth spike, which is inserted into the soil via another cable. The energy boils the water inside the plant and thus destroys the plant structure.

            The result:

            • The plant‘s chlorophyll is immediately damaged, the cells are irreversibly destroyed and die

            • The water supply to the cells is interrupted

            • The plant dries out

            The right amount of energy and optimized ground contact are decisive for the effect: Plants with a high water content and, compared to their leaf mass, with few stems and roots require little energy and are easy to treat. Very dense and woody wild herbs or very large plants require a lot of energy. In these cases, methods combined with mowing, for example, achieve the best results, as the young new shoots carry a particularly large amount of water and therefore direct the flow even better into the plant. Plants with larger rootstocks or rhizomes are severely weakened and sometimes have to be treated several times before they are completely destroyed.

            Idk, if you have the funds and time… or can bring them together in your community… why not just do it and wear friendly looking clothes and act calm and authoritative while doing it? Or… just do it at night while sleepwalking.

            An example of a company that uses electrical equipment mounted on roadway margin mowing tractor type equipment for large scale infrastructure or agricultural use.

            https://zasso.com/control-in-road/

            another

            The crop.zone approach involves a few critical steps. First, a conductive liquid is applied to the Japanese Knotweed. This liquid enhances the plant’s ability to conduct electricity. Following this, a specialised device delivers an electric charge directly to the plant. This electrical treatment penetrates deep into the plant tissues, reaching the roots and rhizomes that are often missed by conventional methods. By attacking the plant at its source, crop.zone ensures a more comprehensive and lasting solution to Japanese Knotweed infestations.

            https://crop.zone/en/blog/tackling-japanese-knotweed/

            Also what about microwaves?

            https://pmc.ncbi.nlm.nih.gov/articles/PMC10818956/

            • Thebigguy@lemmy.mlOPEnglish
              1·
              3 months ago

              Ok I presumed I would measure the resistance like that somehow. I read this: edit: paper

              So I was thinking if low voltages and currents can kill them maybe it would be possible to set up a solar panel/battery set up and run a bunch of electrodes to various plants. I don’t know much about any of this stuff, I started trying to learn electronics a little bit. I’ll read about the microwave stuff but I feel like the electrical method is more approachable.