Results 1 to 10 of 10
  1. #1
    mtbr member
    Reputation:
    Join Date
    Jun 2005
    Posts
    10

    Upset KNOTWEED...Help!

    Does anyone have any suggestions for dealing with or eradicating the invasive species called Japanese Knotweed. It is destroying many of our local trail systems.

    Thanks!

    Mike

  2. #2
    Masher
    Reputation:
    Join Date
    Aug 2007
    Posts
    534
    I had knotweed all around my barn and lawn... I tried hacking it back and it would regrow. Don't pull it up, even small pieces of root will regenerate, now you have 15 plants where you used to have one.

    Was told by a professional invasive person that you need to wait until the plant is at it's weakest, which is just before it starts to flower... then hit all the leaves with roundup.

    I did this and the next spring I only had about 10% of the plants return. That fall, just before those 10% flowered, I sprayed the leaves with roundup. This spring I had about 5% plants return. I'll repeat this process this fall winter and expect I'll get it all on this round.

    That worked great, wish I could thank the guy that told me how to do it...

  3. #3
    mtbr member
    Reputation: Mark_BC's Avatar
    Join Date
    Sep 2012
    Posts
    644
    Oh I've been dealing with that stuff for a while .. absolutely awful. But the upside is you can eat the new shoots.

    Spraying roundup is messy. Easiest way is to get a little drill bit and hand powered drill, then drill a hole in each major stem (they are hollow like baboo), leaving enough space above the septum to hold some fluid. Then fill a large hypodermic needle with concentrated roundup and inject. The hardest part is keeping track of which holes ones you have already injected so you don't double inject!

    You may need to do this next year too, depending on how much you inject.

  4. #4
    Rep Power: Infinity
    Reputation: NateHawk's Avatar
    Join Date
    Dec 2003
    Posts
    12,670
    Quote Originally Posted by Mark_BC View Post
    Oh I've been dealing with that stuff for a while .. absolutely awful. But the upside is you can eat the new shoots.

    Spraying roundup is messy. Easiest way is to get a little drill bit and hand powered drill, then drill a hole in each major stem (they are hollow like baboo), leaving enough space above the septum to hold some fluid. Then fill a large hypodermic needle with concentrated roundup and inject. The hardest part is keeping track of which holes ones you have already injected so you don't double inject!

    You may need to do this next year too, depending on how much you inject.
    Good tip. Yeah, herbicide is the only way to go for this stuff.

    You might want to try picloram (Tordon) as an alternative to glyphosate (Roundup).

    New herbicide offers hope in battle against Japanese knotweed | Environment | theguardian.com

  5. #5
    mtbr member
    Reputation:
    Join Date
    May 2004
    Posts
    1,831
    I hear there's a supper strong vinegar solution you can if you want to go natural.
    There's a big difference between ripping and skidding. Those who skid don't know how to ride.

  6. #6
    mtbr member
    Reputation: donwatts's Avatar
    Join Date
    Jul 2006
    Posts
    88
    Spraykil S-5 Granular herbicide will take it out. SSI Maxim Company, Incorporated
    Trail Builder, Trail Rider,and Trail Protector

  7. #7
    mtbr member
    Reputation: ibadfish's Avatar
    Join Date
    Apr 2012
    Posts
    147
    So knotweed is nothing lie o'dweeds then?


    "The impossible often has a kind of integrity which the merely improbable lacks."
    -Douglas Adams

  8. #8
    mtbr member
    Reputation:
    Join Date
    Jun 2005
    Posts
    10
    Thanks everyone. it is taking over our trail network.

  9. #9
    Masher
    Reputation:
    Join Date
    Aug 2007
    Posts
    534
    Some follow-up... spraying is potentially messy, but if you have thousands of plants drilling holes in each stalk would be a painful undertaking. What I did was to hack them back the first year, and in year two the new shoots did not grow as tall... I sprayed with my back to the wind and walked backward, wore a respirator/mask. It worked. I bought Roundup in the gallon concentrate jug mixed it per the directions and used a backpack sprayer.

    On my drive to work this morning I noticed some roadside plants getting ready to flower - time for the fall spraying!!! Friggin public works crews are inadvertently spreading the stuff all along the roadsides.

  10. #10
    Rep Power: Infinity
    Reputation: NateHawk's Avatar
    Join Date
    Dec 2003
    Posts
    12,670
    Quote Originally Posted by Dave_schuldt View Post
    I hear there's a supper strong vinegar solution you can if you want to go natural.
    That's no more "natural" than anything else, and is likely to be less effective as a targeted herbicide. It will probably damage more than it kills with acute acid burning, but insufficient systemic effects. If you spray concentrated acid, you'd better be wearing more than just a respirator...try full body chem suits. Have fun with that in the woods this time of year.

    Quote Originally Posted by donwatts View Post
    Spraykil S-5 Granular herbicide will take it out. SSI Maxim Company, Incorporated
    I looked at the label of that stuff. That **** will NUKE the forest. Label says it will kill ANYTHING with roots extending under the affected area. Say goodbye to the trees, too. Any land manager permitting volunteers to spread that in the woods doesn't know what they're doing.

    Quote Originally Posted by fishbum View Post
    Some follow-up... spraying is potentially messy, but if you have thousands of plants drilling holes in each stalk would be a painful undertaking. What I did was to hack them back the first year, and in year two the new shoots did not grow as tall... I sprayed with my back to the wind and walked backward, wore a respirator/mask. It worked. I bought Roundup in the gallon concentrate jug mixed it per the directions and used a backpack sprayer.

    Controlling invasives is HARD work. In my area, we deal with Lonicera bush honeysuckle and stiltgrass mostly. The honeysuckle is so pervasive that we mostly just do mechanical removal in a corridor around the trail on our own projects just to keep the density down. Sometimes the land managers themselves will sponsor invasive removal days where we will do more involved work with other user groups. Stiltgrass primarily gets spot sprayed, but also gets dug out on a more limited basis.

    On my drive to work this morning I noticed some roadside plants getting ready to flower - time for the fall spraying!!! Friggin public works crews are inadvertently spreading the stuff all along the roadsides.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •