The yellow peril

[Palustris]

Just read Shelagh'S article about Oxalis cornuta, aka Bermudan Buttercup. It was probably the second most common herbaceous plant in this garden when we moved in (after Bindweed). Whilst it is still here we do seem to have reduced it in quantity to a nuisance rather than a plague.
So how?
First of all we did use Roundup which worked for us. Try adding a little washing up liquid to the weed killer spray to make it stick to the leaves. Now we have planted up the garden that is no longer an option . Secondly and still being done I use a Flame Gun on it where it appears in the paths, gravel etc. Obviously one has to be careful not to damage any plants nearby. Thirdly we dig out every one we see with a clump of soil rather than trying to just remove the roots.
It really does need careful watching. It is best practice to get it out before it flowers. We have found that it goes from flower to seed almost overnight and each seed pod contains a lot of dust like seed. The roots have tiny 'bulbils' on them so any left behind will regrow. We have reduced it by about 95% by what we have done.
The saddest thing of all is that it appears to be included in peat free composts as we have found it growing in pot plants which have never been anywhere near the stuff in the garden.
Finally NEVER NEVER NEVER EVER put the bits in the compost heap. We put it in the bin (not the green waste bin either).
Sorry to say but the advice is eternal vigilance!
Best of luck with it.

[Tristan_He]

Thanks Palustris. These kind of posts are some of the most useful on the forum. It's incredibly valuable to be able to tap into the experience and wisdom of others.

Tristan

[MarcR]

Thanks Palustris. These kind of posts are some of the most useful on the forum. It's incredibly valuable to be able to tap into the experience and wisdom of others.

Tristan

Tristan,

That is so very true.  Yet surprisingly few will take heed. [Perhaps serious gardeners are an exception ]

[partisangardener]

Which Oxalis is meant Oxalis pes caprae or Oxalis corniculata?
I could not find Oxalis cornuta.

[Vinny 123]

One of the simpler ways of using glyphosate on small weeds, especially creeping ones, is to use a very small sponge or wad of cotton wool, place one hand under the weed and wipe using the other. WEAR RUBBER GLOVES.

Some persistant deep-rooted weeds are actually very easy to get rid, if labour-intensive for a while.

When I moved here, the place was a sea of thistles. I dug the ground over, removed everything as far as possible and then waited. Once the shoots were 1-2 inches out of the ground, big enough to grip, I pulled them up - after no more than 3 re-shooting attempts, they disappeared.
I used to get in from work, make a mug of tea and spend 10-15 minutes plucking thistles each evening - it didn't take very long.

It ought to work with bindweed, docks and a few others. I think that I'd use a knife for docks, severing them a few inches underground.

Not appropriate for an acre that is infested, but not a vast chore on even large beds.

Anyone concquered mare's tails/catweed/horsetails/whatever you want to call them - Equisetum?

[MarcR]

Here in the USA I use either VAPAM or methyl bromide under tarp.
I imagine that if insecticides are banned in the UK, then VAPAM and methyl bromide probably are as well.

Of course this can only be used before planting the area to be treated.

After an area is planted the only thing I can think of, Vinny, is your suggestion of relentless weeding.

[Vinny 123]

Here in the USA I use either VAPAM or methyl bromide under tarp.
I imagine that if insecticides are banned in the UK, then VAPAM and methyl bromide probably are as well.

The only use that I recall for methyl bromide for fumigating imported and/or stored grain and similar bulk organic goods. It is indeed banned in the EU/UK, and hs been for quite some while.

The active ingredient in Vapam (a name unknown to me) is currently metam sodium (also known by various other names). It is "unpleasant" to both humans and the environment but, surprisingly, currently licenced for use in the EU/UK, probably only for professional use though as it isn't a chemical that I recall hearing about in connection with amateur-use garden chemicals.

Weeding need not be relentless over a long period, just make sure it is done often enough that rootstocks have no time to build-up more reserves. Thistle roots severed during digging will break several inches down and in friable soil, new shoots will usually break where they join the old root when pulled.

[Palustris]

I did once get rid of Equisetum from our second garden. It took a long time though. I pulled out every stem I found ever day  when I came home from work. After about 5 years or so it gave up. Mind that was only a very small patch of it. 1 sq mt at most.

[MarcR]

Vinny,

In the course of doing the undergraduate work for my teaching credential, I completed an AS in Ornamental Horticulture to relieve my boredom.
Though I never used it to earn a living i got licensed as an agricultural pest control operator.  I therefore have access to things not available to most gardeners.
Here in the USA Malathion is available to anyone; but Methyl Bromide is not.
VAPAM is available without a license in some states but not in others.

[Vinny 123]

I did once get rid of Equisetum from our second garden. It took a long time though. I pulled out every stem I found ever day  when I came home from work. After about 5 years or so it gave up. Mind that was only a very small patch of it. 1 sq mt at most.

LLLOL! Only 5 years   

[Vinny 123]

Though I never used it to earn a living i got licensed as an agricultural pest control operator.  I therefore have access to things not available to most gardeners.
Here in the USA Malathion is available to anyone; but Methyl Bromide is not.
VAPAM is available without a license in some states but not in others.

I have no idea EXACTLY how anyone would get a pesticide licence here in the UK, in detail, but suspect that it isn't too difficult for anyone with any kind of common-sense. The downside would be the cost of taking the course.

I strongly suspect that malathion is avaiable freely here too, but not for horticultural use, so it depends who's looking   

[MarcR]

I am so glad that here very little is restricted for horticultural use.

some things may only be applied by a licensed operator, but a homeowner can be or hire a licensed operator.

[shelagh]

Brian has found the first small pieces of the Yellow Peril this week. Here we go again 

[MarcR]

The only use that I recall for methyl bromide for fumigating imported and/or stored grain and similar bulk organic goods. It is indeed banned in the EU/UK, and hs been for quite some while.

Here both VAPAM and Methyl bromide are used as area soil sterilizers. they kill everything present including beneficial bacteria and microrhizae.
after using one or the other the good organisms need to be reintroduced.