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Invasive Tree of Heaven.Anyone else experienced this ?

(12 Posts)
Washerwoman Thu 29-Jul-21 07:14:40

I'm absolutely sickened that our very big mixed shrub and perennial border has been invaded by a huge network of roots that keeps throwing up suckers .It turns out after some detective work it's due to several Tree of Heaven saplings that have been growing through the neighbours side if the huge beech hedge between us.Fortunately we get on very well and they are going to apply a systemic herbicide asap but unwittingly a lot of damage has already been done by them cutting down several of them.They didn't realise this is the worst possible thing to do as the tree responds by throwing out runners and suckers everywhere if you cut them before treating them.I hate any use of chemicals but it seems this is the only thing to do.
I spent hours yesterday pulling out as many as possible but were going to lose a considerable number of established plants as the root systems are so enmeshed with these runners covered in nodes ready to sprout.I even dreamt about triffid like plants last night !Has anyone else experienced this and can you reassure me it can be cleared.The problem is even if we dig out all the border getting any left under the hedge is impossible and I loathe to replant my border until I feel we've eradicated it.
Neither we not the neighbours had ever heard if this species before. Indeed they didn't even realise what they had growing in the hedge.They keep the garden very tidy but aren't plant people where's we are and have spent a lot of time -and money -on ours so I feel pretty despondent this morning as I've only tackled a fraction of the bed so far.

Katie59 Thu 29-Jul-21 07:56:51

Not using chemicals means digging out and exhausting the root system on both sides of the fence over several years, so not really practical.
Careful spot spraying or painting with glyphosate will kill the root system, although you will have to repeat the treatment frequently. We have a similar problem with invasive bindweed so I can sympathize with your task.

Washerwoman Thu 29-Jul-21 08:08:34

Thanks for your reply Katie.Yes unfortunately I am going to have to spot treat some roots aren't I?.I would put in the many hours digging out repeatedly but it's such a big network I think it needs something more drastic.I sympathise with the bindweed .We get that coming in from the other neighbours side but as it's mainly in the hedge on the wildlife area at the bottom and it pulls out relatively easily -compared to this !- I tolerate a bit .I'm waiting for the weather to clear up and tackling another section today.

Newquay Thu 29-Jul-21 08:31:15

I asked DH about this-he’s a very experienced gardener. It’s stags horn sumach. Apparently we were given one years ago and he kept it in a pot for that reason-too late for you now, of course sadly. You will have to be brutal apparently

jusnoneed Thu 29-Jul-21 09:43:45

I had the same problem a few years ago with a stags horn in neighbours garden, I sprayed each new sucker when it appeared with a glyphosate weedkiller and pulled out whatever root I could. It took some time but eventually the tree died. They wondered why it had given up the ghost but I never told them!

BBbevan Thu 29-Jul-21 11:14:40

My dad had one that threw suckers into his garden. It came from next door. He put weed killer on the suckers and eventually the whole tree died. He never told a soul.

25Avalon Thu 29-Jul-21 11:22:17

Sorry to hear of your problems Washerwoman. I avoided growing this tree as I read it suckered, but had no idea how bad it was. Although it doesn’t help you thank you for the warning. I certainly won’t grow it. Hope you manage to get rid.

SpringyChicken Thu 29-Jul-21 15:27:04

As both you and your neighbour are willing to wage war on the suckers, you should be successful in exterminating the tree. Be vigilant and look for suckers every week and treat them immediately. It takes only one missed sucker to perpetuate the problem. Copper nails banged into the trunk may also help kill it off.

Washerwoman Thu 29-Jul-21 20:40:59

Thanks for your replies and advice.I have just cleaned up from another 3 hours digging over and pulling up some frankly huge roots.Feeling a bit overwhelmed.I have dug up my perennials like astrantia and geums etc,split and replanted after checking the root ball for traces of the Sumac root in the hope that I can salvage some of my plants.Does anyone know if it will regenerate from a small chopped up bit ? Or isnit just roots from the trees that I have missed that will cause future problemsI can't possibly get every little piece out.I have put quite a bit of stuff in a bag for the tip as the roots were so intertwined.
I was shocked to see this plant for sale on the Crocus site ( which I use a lot) with absolutely no warning of how invasive it can be.Made me cross actually.

MissAdventure Thu 29-Jul-21 20:45:56

It sounds so delightful.
I've never heard of it before.
Off to google.

aggie Thu 29-Jul-21 21:05:33

I went to google this and first thing that came up was this thread 🤣🤣🤣

MissAdventure Thu 29-Jul-21 21:07:46