Himalayan Balsam is one of the UK’s fastest-spreading invasive plant species. Residents and volunteers teamed up to uproot the plant at Prestwich Clough’s tenth Balsam Bash.
Bury Council has launched ‘Bury’s Big Balsam Bash’ for its second year to combat the spread of Himalayan Balsam. The plant was introduced to the UK in 1839 for its attractive pink flowers. However, since 2017, it has been on the UK government’s list of ‘invasive alien species‘ due to its negative impact on the environment.
The ‘balsam bashing’ event at Prestwich Clough cleared roughly 300 metres of the invasive species. Twenty participants, ranging from gardening experts to complete beginners, took part in the ‘pulling, snapping and stamping’ the Himalayan Balsam.
Jenni Lea from Lancashire Wildlife Trust explained how ‘balsam bashing’ works: “We’ve been hand-pulling the balsam. That involves pulling it up by its roots, snapping the stem between the root and the first node, popping it on a pile on the ground and giving it a good stand. So, pull, snap, stamp.”
Gary Hamilton is a member of the Friends of Prestwich Clough. He said: “It’s my first year doing the balsam bash. It was new to me as well as to everyone else. There’s been about ten [sessions] since April, so we’re getting used to it.
“We see a massive difference by doing it. When we come back to do a second check, we see new growth coming from new plants like nettles and brambles.”
Balsam can be identified by its translucent green stems. In the summer, it grows densely, and often near waterways. Himalayan Balsam can reach up to 3-metres tall with trumpet-shaped pink flowers and green seed pods that turn brown when they ripen in autumn. Each pod can contain up to 800 seeds and eject the seeds up to 7 metres away.
Lea explained the negative impact Himalayan Balsam has on the environment. She said: “It’s an invasive, non-native species which means it takes over and crowds out all the other native plants, which reduces biodiversity so that’s a big problem for our native wildlife.
“There’s a lot of pollinators and invertebrates that can’t feed on it or use it to plant eggs. It’s really important to have a lot of different species. Balsam stops that.”
According to the Non-native Species Secretariat (NNSS), the spread of invasive, non-native species has been linked to 60% of global biodiversity loss. The State of Nature Report shows that the UK’s biodiversity has already faced a staggering decline, with the distribution of 64% flowering plants decreasing since 1970.
Another aspect of the environment effected by this plant is the soil, particularly by water ways.
“The other problem with balsam is soil erosion on our riverbanks.” Lea shared. “Balsam is shallow-rooted; it dies back in the winter, leaving riverbanks exposed.
“Then we get lots of rain, water levels rise, and the soil then washes away, because root structures hold soil together. The banks don’t have that because of the balsam. But a seed can stay viable for three years in the soil so the hard work from today isn’t over yet.”
Current estimates show that invasive species such as Himalayan Balsam cost the UK £1.9 billion per year to manage. While Himalayan Balsam can be hand-pulled and destroyed on site, other invasive species such as Giant Hogweed require specialists to remove the plant.
Balsam bashes are taking place in Bury until the end of August. More information on getting involved can be found here. Lancashire Wildlife Trust also host events and volunteering opportunities, which can be found here.