Using lime to control horsetail?

[longpig]

Hello!
I have a major horsetail problem on my allotment -- I've covered part of the plot in Mypex but the horsetail is bursting out of the edges and it pops up in all the beds I've dug. I have been laboriously pulling it up but it's starting to seem like the only thing I do on the allotment and I'm wondering about other solutions. I've been reading a bit on the internet which suggests that using lime to make the soil more alkaline can be effective in controlling it. I was wondering if anyone had had any success with this approach? It sounds a bit too good to be true!

[fishpond]

Can't you use weed killer?

[BertieFox]

It is too good to be true! We garden on very limy soil but it still comes back every year. Weedkillers do not work, other than knocking it back a little, but you are supposed to 'bruise' the foliage and then use strong glyphosate. But even if you do that, it will still be back.

One year I totally covered a badly affected patch with black plastic and left it in position for over a year. When I removed it, the ground was totally clear. As soon as I started to cultivate the bare soil, it was back in a few weeks. I built a patio and covered it with weed suppressing permeable membrane and a thick layer of gravel. The horsetail came through all over the place, but relatively thinly, breaking through the membrane. I pulled it out as soon as I saw it, did this for two years, and now the patio is free of it.

It grows freely at the bottom of our garden (which slopes from north to south) where it is very moist. At the top of the garden where it is far drier, it is easy to control and hardly in evidence. I think this must be the key, somehow lightening your soil and making it drier.

If that doesn't work, I find pulling it out after it has grown to a reasonable size but before it starts to form spores, is most effective. You can often pull it out that way with a good bit of black root attached and it takes longer to come back.

As weeds go, it is not the worst, so just persevere, knowing it is an ancient plant that has evolved to resist all methods of control!

[longpig]

From what I've read there are no weedkillers that are particularly effective against horsetail. I've read lots of threads that say the only solution is to keep on pulling it up, which I will continue to do! I was just curious to know if anyone had managed to control it by using lime and improving the soil... as recommended here:

http://www.maine.gov/dacf/php/gotpes...il-swanson.pdf

[longpig]

Thanks BertieFox -- sorry to hear you have a problem too! It does seem fractionally better in my raised bed, which has lighter, dryer soil. There's obviously no miracle solution, sad to say...

[marchogaeth]

You know in movies when they talk about a "silicon based life form"...........well, unless I've got it completely wrong, horsetail is very, very high in silica you have to just accept it's an alien life form which landed here at the time of the dinosaurs (in fact before). We are just a passing annoyance as far a sit is concerned - "lime? Pah! It remembers when it was just shells!" When they work out how to get the mother ship working again they will all disappear overnight and the world will be a sadder place without them.

(OK end of delaying tactics - I have to go and start the VAT/Tax returns and student loan applications. I also know silica and silicon are completely different before the chemists start. )

[marchogaeth]

Read the paper and everything they say is correct but I think they are really starting with a wet, acid(probably pH 5 or less) bog. We actually created one next to our pond in which to plant horsetail! It doesn't spread from there even though our soil is naturally acid an relatively damp.

This doesn't explain why people have it in their quite nice well cultivated gardens though does it - unless it has adapted to those conditions. Nothing likes being pulled up and weakened all the time so that seems like the best plan. If you want to try a frightening experiment, take one of the stems and split it into all its little bits and sprinkle them on some nice damp peat and watch what happens. Moral - don't leave any bits behind, don't put it in the compost bin. (And sleep with the light on!)

[sparrow100]

It isn't supposed to like rich well drained ground, which is why it loves my boggy, compacted plot. I pull it out as soon as I see it. Ammonium sulphamate works effectively on it and degrades into nitrogen. It's sold now as a compost accelerator not a herbicide. It's amazing how many trip hazards there can be on the way to the compost heap...

[Knight of Albion]

Horsetail is one of the most ancient plants on the planet and it hasn't survived that long without good reason!

As for going thermo-nuclear with the weed killer. Two things 1) It is deep rooted, so weed killer is unlikely to get down that low. You'd have to literally flood the ground to get it to soak down that far. And 2) You're going to be growing food to eat off that ground remember....

The best way of controlling it is to pull it up or fork it up any time it puts up a new shoot. Much like with bindweed, it might seem like a thankless, even hopeless task!, but eventually you will get the better of it.

[lottie dolly]

the wretched stuff is full of life this year,never seen it so bad,and it not been rotavated either,

[Snadger]

Here's what the RHS have to say about it.

https://www.rhs.org.uk/advice/profile?PID=257

Apparently its good as a pan scourer!

If you drown it in a water butt it will release all those minerals it has dragged up from the nearest coal mine!

[longpig]

If you want to try a frightening experiment, take one of the stems and split it into all its little bits and sprinkle them on some nice damp peat and watch what happens. Moral - don't leave any bits behind, don't put it in the compost bin. (And sleep with the light on!)

That's something I was wondering, as I'm considering strimming then covering with cardboard/manure. Can it actually regenerate from the top growth or only from the rhizomes...?

Thanks to everyone for all the interesting replies -- the forums are such a great source of information!

[marchogaeth]

Every little segment is capable of life - Gremlins and water...............

[BertieFox]

The type of horsetail you plant in a pond or on the margins is NOT the same invasive horsetail you get in the garden.

This is either Equisetum scirpoides, or Equisetum japonica, while 'wild' horsetail is E. hyemale.

[Marcusp]

The only weed killer thAt was designed to kill it and proven.
Not cheap though
https://m.youtube.com/watch?v=CE855jSghPk