Invasive bamboo from neighbour's garden

[treatbeata]

When we bought our house in 2018, the homebuyer survey mention an invasive Black Bamboo plant in a neighbour's garden. It is a large clump next to the boundary fence and some vertical shoots were coming up on our side of the fence at the boundary line. The seller cut them back and sprayed them with weedkiller before we moved in.

Since then, more have grown each year, some through loose joint lines in our patio. I have cut and sprayed, and also informed the neighbour. A few months ago he got a tree surgeon to prune the plant and cut the horizontal rhizomes extending out from the main clump (at least the ones he could see), but the problem re-occurred this summer.

Then, a few days ago, I was shocked to see bamboo leaves appearing under the bargeboard of our kitchen extension, which is approx 1.2m from the boundary fence. I've cut them back, and I'm waiting to see if they reappear. As bamboo doesn't seem to be an airborne propagator I'm terrified in case there is bamboo growing vertically up through my cavity wall. There is no other sign of damage (yet). I have informed the neighbour again and adked him to remove his plant, but he is very reluctant to do so. He has said he will consult an expert about containing it instead.

Bamboo isn't formally classified as a controlled invasive species, but the Property Care Association are raising awareness of it as a potential future candidate for the list and are comparing its potential for structural damage to Japanese Knotweed. I know there have been cases of people sucessfully sueing neighbours for property damage, but we hope we never have to do that.

Any advice?

The bargeboard, actually on the (presumably) single storey roof level?

Do you have legal advice with your house insurance? I’d give them a call if you do, they may be able to help.

We had a neighbours property start to impact our garage and our insurance sent a surveyor round really quickly. We didn’t have to do anything else or pay anything and the neighbour took action pretty swiftly. I’m assuming our insurance got in touch with his insurance and told him to sort it. Worth a shot.

Yes, at single storey roof level. From what I've read, bamboo propagation isn't airborne, so I'm now waiting with trepidation to see if the leaves reappear in the next few days.

In the meantime, the neighbour is consulting a bamboo expert, about ways of containing the plant, but not a surveyer.

I think it may be too late to contain it, because the rhizomes under my patio may have self-rooted.

In which case your insurance may want his insurance to deal with the resulting damage, the removal of it from your property and any repairs. Have hope!

Bamboo is bad news. You're right, they're not airborne propagators. They spread horizontally underground like slow-motion wildfire, iyswim. You destroy those you see overground and think you've got rid of them. Suddenly you see new clumps appearing a few metres away; they don't respect boundaries and shoot up everywhere. I've had bamboo shooting up on public paths from behind my fence (mine is an end of terrace house) and even pushing up the tarmac on the main road.

Over a few years I fought a losing battle with them. I've had people coming to spray weed killer and all kinds of chemicals but to no avail. Then one day, I struck on a new idea - it's actually very simple and cost next to nothing.

I had observed the destructive power of ordinary household bleach. So I set out first to remove as much as possible all the underground clumps and roots that I could lay my hands on. I then mix some household bleach with a fair amount of water in a watering can and direct the mixture to where I think there might be roots and clumps that's not immediately visible including cracks on the ground, pavement, paths, etc. Make sure you don't water the area where other plants grow; you'll kill them as well as the bamboo. Repeat this process a few more times at short intervals. What you'll see days or weeks later are dead roots and clumps in the ground. You may have to do this over a couple of seasons.

I don't have a single bamboo leave or root for the last five years now. The cheap 2-litre supermarket own brand of household bleach will do nicely. Talk to your neighbour first before you embark on this mission. Good luck!

Thanks for everyone's advice. I thought it was worth posting an update, in case anyone else has a similar issue. After a bit of persuasion, my neighbour agreed to consult a specialist weed control contractor, accredited by the Property Care Association. The consultant confirmed that the so-called "clumping" bamboo had started to spread. He said it is a variety that is often mis-sold as clumping, but starts to spread later (in this case after about 20 years of growth).

A herbicide treatment plan has now been started, and the bamboo main plant will be removed in the winter. Once it has gone, the contractor may need to return each spring for a few years, whenever new shoots appear. Interestingly, their advice is to not immediately remove any vertical shoots, but to let them grow a bit, because then they will absorb the herbicide more readily. It is a type of herbicide that circulates within the plant's root system, so by treating the verticals, the rhizomes underneath are killed off. (He said if you remove the verticals without treating them first, then the rhizomes may become temporarily dormant but then shoots may reappear after a couple of years).

Fingers crossed, this may now be resolved without any need for legal involvement, though I'm still keeping a nervous eye out for any more leaves appearing under the bargeboard.

Hi, I wondered how things are going now @treatbeata ?

My neighbour ditched the consultant after the first visit on the grounds that he was too expensive, and used a local guy instead. He took the main bamboo plant out, including the rhyzomes under my patio where the flags were already lifting loose, and treated the ends where he cut it with the herbicide. That was last September and no new shoots grew this Spring, but I'm keeping a eye on it. The bamboo consultant did say if you take it out too aggressively then it can go dormant for a year or two before re-emerging, so fingers crossed that won't happen.

Thanks, I hope it works for you