Calling for a garden weed expert

[The late XV105]

What on earth is this invasive and unwanted pest, please, and how can I kill it without digging it out? Garden location is UK West Midlands.





Before I laid the slate chippings you can see in the photographs I took care to remove all visible weeds, kill (or so I thought) any that remained in germinating form, and then lay a tight mesh weed clover. This wretched thing just punches straight through it.


TVM,
XV

[DX Wombat]

It's Horsetail, a very ancient plant from the time of the dinosaurs. A flamethrower applied at regular intervals should keep it in check. Further advice here.

[The late XV105]

Thank you

Thank you DX.
An impressively fast and helpful response.

As I don't want to dig up the garden (not laze but more practical reasons) it seems that I will have to:

1. Cover my newly laid grass with polythene sheet
2. Remove all the slate chippings on to the sheet
3. Lift the weed barrier sheet
4. Remove all visible evidence of Horsetail
5. Spray the ground thoroughly with glyphosate herbicide
6. Replace the weed barrier with several layers of strong black (no light) polythene sheet
7. Re-lay the slate chippings
8. Stand by with a flame thrower!

Cheers,
XV

[OFSO]

All of which raises the question: define a weed.

One man's weed is another man's beautiful plant.

Perhaps definitions could be: something you don't want growing there...... something that comes back no matter what you do to it........something that thrives healthily on no earth and little water when everything around it is dying out......

[green granite]

Spray the ground thoroughly with glyphosate herbicide

Errrrrrr no, glyphosate is only effective on growing plants, it becomes inactive in contact with soil, just spray it on the weeds but you may need to redo it after a couple of weeks on some weeds to ensure killing them.

[fernytickles]

Might be worth trying a kettle of boiling water? I've found using that a couple of times seems to kill some weeds right back.

[Slfsfu]

XV105 – . Sorry to add to your problems but, between 7 and 8 you need to add something like “Spores from the pesky stuff will blow between the slates, germinate in the damp conditions and start to go again and again !!!

As for underlay sheeting I’ve found “terram” to be quite good. You can get smaller rolls that that mentioned in this site Greenseal Pond Liners & Green Roofs

“...The leaves have a waxy coat and this is what makes them difficult to eradicate. However, glyphosate weed killer will eventually kill the plant after several applications. Anything with Ammonium Sulphamate would do the trick as well.....”

It's a real b#####d !!!

[Linedog]

Just spraying it with glyphosate will not work as horsetail to give it it's correct name, (marestail only grows in water), has a natural coating of silicone so the weedkiller will just run off it. I have an allotment and we are constantly fighting this stuff.

For the weedkiller to get through you need to bruise the foliage by giving it a good thrashing with a stick or similar.
Glyphosate can take up to three weeks to start working. Then give it a 2nd dose while it is in a weakened state.

Good luck with it.

[vulcanised]

Console yourself with the knowledge that it's not Japanese Knotweed.

[G-CPTN]

Japanese Knotweed.

I am fully-trained (and certified) to inject industrial-strength glyphosate (10 times the concentration of the neat stuff you can buy in the shops) into the stems of Japanese Knotweed.
This has proven to be almost 90% effective in killing the plants - we have to wait for the regrowing stems to achieve a size capable of accepting the injection needle.

As the stands are adjacent to a river, it's not permitted (by the Environment Agency) to spray, and mechanical methods risk fragments being washed away downstream during flood conditions, so we have developed the injection treatment (which is successful - with only minor regrowth from the rhizomes):-
Japanese Knotweed Removal by Glyphosate Herbicide Injection

[BOAC]

I am fully-trained (and certified) to inject industrial-strength glyphosate (10 times the concentration of the neat stuff you can buy in the shops) into the stems of Japanese Knotweed.

- my hero! All my life I've been looking for someone like you....................not sure about the 'certified' bit, though

[DX Wombat]

Fernytickles, I find that works sometimes as well. It's a most effective method of getting rid of vine weevil grubs in pots of compost. The formerly resident plants are usually dead anyway as the grubs have eaten their roots.

[The late XV105]

So now I know that the bloody pest in my back garden is - Japanese Knotweed, confirmed by Google Images!

Rightly or wrongly - and I'm nowhere near a river - my "solution" is to let the thing grow and then spray a systemic insecticide on to the leaves. The plant then withers and dies within a week or two and doesn't come back. Since doing this the incidence in my back garden has fallen from hundreds of growths a year to a couple of dozen.

[probes]

Stand by with a flame thrower!

that's probably the best alternative if you don't want to dig, dig and dig - and dig deep. Some friends have done it in their Alpine gardens and left no rock unlifted - lots of trouble, but if you don't like it... Boiling water might work for a while (better than pesticides), but it won't kill the roots. Plastic and pebbles might work, if you manage to prevent the roots escaping the area.

And if nothing works, you might try to look at it from a different angle and decide it's beautiful. No trouble growing either, real blessing!

[G-CPTN]

Originally Posted by BOAC

- my hero! All my life I've been looking for someone like you.

Someone has to do it . . .

We have Japanese Knotweed adjacent to the highway bridge across the river - a bridge that dates back many centuries an was the only bridge to survive 'the great flood' of 1771:- Corbridge Bridge

A team of volunteers from the village are determined to prevent the Japanese Knotweed from percolating into the foundations where it would destroy the structure.

Environment Agency - Japanese Knotweed

[DX Wombat]

So now I know that the bloody pest in my back garden is - Japanese Knotweed, confirmed by Google Images!

It is NOT Japanese knotweed. It's Horsetail!
Japanese knotweed:


Horsetail:

[tony draper]

Sounds like it would have been easier to get rid of the Dinosaurs.

[vulcanised]

you might try to look at it from a different angle and decide it's beautiful. No trouble growing either, real blessing!

Not exactly! I'm sure G-CPTN will be able to confirm whether I'm correct or not, but I believe JK is like a notifiable disease and you have to inform the local council of its presence and get an accredited contractor to remove it.

[G-CPTN]

If, indeed, you do have Japanese Knotweed in your garden (in the UK) then you should eradicate it, as the presence (in the vicinity of buildings) can result in refusal to issue a mortgage (should you want to sell or remortgage your property).
Mortgages refused over invasive weed - Telegraph

Homeowner turned down for mortgage due to Japanese Knotweed in garden - Telegraph

moneysupermarket.com community - Japanese knotweed

[The late XV105]

It is NOT Japanese knotweed. It's Horsetail!

Front garden = Horsetail
Rear garden = Japanese Knotwood