Invasive non-native species in and around Walton le Dale primarily include problematic riverside plants like Himalayan balsam and giant hogweed, alongside aquatic and woodland threats managed locally.
- Himalayan Balsam: Chokes native riverbanks along the River Darwen and River Ribble.
- Giant Hogweed: Found near local river confluences; poses a serious public health hazard due to toxic sap that causes skin burns.
Currently, these problems aren’t being dealt with particularly well locally.
It was interesting to note that a well-know YouTuber visited the area to specifically look at the Himalayan Balsam and Giant Hogweed. He recently release tow separate videos that talk about each of these plants and how they are effecting our local environment. The channel is ‘Leave Curious’, on which are published hopeful restoration stories, and more.
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Britain’s Most Dangerous Plant Is Spreading
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This Explosive Plant Is Invading Britain
There is a plant growing across Britain right now that literally fires its own seeds through the air like miniature missiles. And it might look completely harmless with its sweet perfume and delicate pink blossoms. But this plant carries a secret weapon, an explosive mechanism that forcefully shoots its seeds through the landscape to colonize entire river systems. It smothers native wildlife, replacing rich, diverse river banks with a single impenetrable species and leaves the ground beneath it literally crumbling into the water. It’s pretty bad right here. Look at it. It is just rife with invasives here.
Over there is where we film the hogweed. You can see the giant hogweed over there. It’s this tall stuff. But today we’ve come back for something else. And the plant in question is Himalayan balsam, So it forms in these dense thickets here and it’s disappearing down to the river. It kind of smothers everything out. Oh, but not the hogweed. You can see the hogweed is getting away there. There’s a huge patch of it back that way which we’ll take a look at in a minute. I’m just just going to see what’s up here. Look at these giant hogweeds. Stay away from them, please.
So, we’re just outside of Preston (in Walton le Dale). This is the River Darwen, which then feeds into the River Ribble. And, yeah, it’s pretty bad here. So, just looking at this plant, you could be forgiven for thinking that this is one of Britain’s most beautiful flowers. And they are, very pretty. Bees love them, too. So, how do you identify them?
Well, the stems, they’re hollow and they’re a reddish pink, almost looking like a giant juicy stalk of celery. These ones here are quite young. Look, there’s a fairly large one down there. Look. See? And the leaves, well, they are long spear shaped with
fine sawlike teeth along the edges, but the dead giveaway are the flowers. They’re delicate helmet shaped blossoms that range from a pale pink to a deep purplish magenta. And they look a little bit like wild orchids.
Now, while it does look gorgeous and the the flowers, they do smell rather sweet, do not underestimate what this plant is really doing to Britain’s ecology. So, what makes a harmless looking pink flower such a threat? Well, Himalayan balsam grows in dense, impenetrable monocultures. In early spring, its seeds germinate weeks ahead of our native flora. It shoots up at a terrifying speed, forming a thick canopy that blocks out nearly all sunlight. Native plants like nettles, ferns, and wild garlic don’t stand a chance, and they are literally smothered and starved of light before they can even establish.
Now, if you’re standing here on a summer’s afternoon like today, you could be fooled into thinking that this is good for wildlife. You’ve got bees buzzing around it, other pollinators going into the flowers and taking the nectar. But the truth, the truth is very different. So, while bees clearly benefit from this rich nectar, ecologists worry that such an overwhelming food source pulls pollinators away from native flowers like fox gloves and willow herb, leaving them unpollinated. And worse still,
while generalist bees actually visit and pollinate these flowers, um, they don’t really fulfill that niche for a lot of our specialist insects and pollinators here. Think of these Himalayan balsam patches as like a high sugar junk food zone that ultimately starves out the wider ecosystem.
Problems like this can’t be solved by one person. They take all of us working together. That’s why
I’m building something to help people become part of the solution. I’ll tell you more about it later, but if you’d like to follow it from the beginning, there’s a free email list which you can join below.
These monocultures turn what could be a diverse native ecosystem into what is an ecological desert that’s wrapped up in these pretty pink flowers. But here’s the here’s the really tricky bit about this plant. Wonder if I can get one of these to go. Oh, there you go. These are the exploding seed pods. Now, might be a little bit early in the year, but some of these are starting to turn into these green almost ribbed seed pods. And as these pods dry out, tension builds inside its walls like a tightly
wound spring. The tiniest touch from a passing animal or a heavy raindrop or a hiker’s boot causes the pod to split apart, curling backwards in a millisecond and firing the seed several meters through the air.
Oh, that one exploded in my eye. And it’s this seed dispersal mechanism, which means that a single plant can conquer meters of ground. But when you couple that with having waterways which are carrying the seeds around, it’s no wonder that it’s getting out of control. And here’s the other catch with it. While it forms these kind of dense areas in the winter, it completely dies off and then you’re just left with, you know, complete bare ground. And a lot of that bare earth can then just be washed into the rivers and that will smother all of the fine gravels which a lot of fish species and invertebrates rely upon. And here’s an example of that bare earth which results from just the domination of the balsam. And you just get this like really loose soil.
So how did Himalayan balsam get here? Well yet again like many of our most invasive non-natives it was the Victorians. Its native home is thousands of miles away in the damp valleys of the western Himalayas, stretching across India and Pakistan. In 1839, plant hunters brought seeds back to the UK.
Victorians were instantly captivated by its vibrant orchidlike flowers, rapid growth, and of course, the fun quirk of his exploding seed pots. It was sold as a cheap, high impact ornamental plant for grand country gardens. Because it was so easy to grow, gardeners swap seeds and land owners planted it along estate streams to look pretty. And it wasn’t long before it made its way off out beyond these gardens and into our river systems with these exploding sea pods, you know, next to rivers. They would just be carried downstream.
So, looking at the scale of this plant, can we realistically beat it? Can we eradicate it? And I think the answer to that is, you know, it’s not going to happen overnight, but we can absolutely start to turn the tide on this thing. But we must be real about how aggressively this plant spreads. Reports show that it increases by 645 square kilometers each year. That’s an area nearly half the size of Greater London. It’s currently conquering damp river banks and woodlands across the UK. And while this does sound like an unstoppable ecological disaster, I do believe that we really can get a handle on it. And that’s for a few reasons.
Unlike other non-native invasives, Himalayan balsam is actually pretty straightforward to deal with. It’s not that much of a problem. They have laughably shallow root systems. I mean, look at that. Just comes out almost too easy. And unlike giant hogweed, you can actually walk up to to this one and pull them straight out without any worry that you’re going to get a burnt. And unlike other non-natives, the seeds, they don’t lie dormant in the soil for decades. I actually think it’s just a a few short years. So if you have a coordinated approach between groups across catchments, you can really begin to turn the tide on this. And the other thing is that it’s, you know, it’s volunteer friendly communities.
Volunteer groups go out and they do what’s called balsam bashing, which is where you want to get in before the seed pods change. I think we’re a little bit late now because a lot of them are bursting, but you want to get in before the seeds develop into this explosive state. And uh yeah, you just want to bash it down and pull it out. One thing I’ve learned from making these videos is that awareness alone isn’t enough. If we’re going to restore nature, people need a genuine way to become part of the solution.
And that’s exactly what I’m building. Every month, we’ll explore a different aspect of nature restoration. We’ll learn from the people leading it, take one meaningful action together, and together we’ll also fund the work that’s making a real difference. If you’d like to be part of this from the very beginning, just join the free Leave Curious email list. It’s joinleavecurious.com
You can either scan the QR code with your phone or use the link in the pin comments or description of this video. Have you ever partaken in some Balsam Bashing or would you like to try it? Let me know down in the comments.
On screen here is the membership. Do go and check that out. And here is a video for you to watch next. In the meantime, thank you so much for watching. Leave curious.