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Six Acre Meadow Balsam Bash – Hogsmill River, in London Rivers Week

June 25 @ 10:00 am - 2:00 pm

A volunteer cutting back balsam

Activity Description: Join us during London Rivers Week at Six Acre Meadow to help remove the invasive plant, Himalayan balsam.

Himalayan balsam is a big problem for river banks up and down the country. In addition to competition for pollinators, native plants must also compete for light, nutrients and space, leading to an overall reduction in biodiversity. Moreover, the fact that the balsam dies back in the winter means that it leaves river banks bare and susceptible to erosion, and the dead leaves and stems can also cause blockages, which lead to flooding.

What’s more, each plant can produce up to 800 seeds per year – and one plant can propel copious amounts of that seed a distance of up to seven metres. This seed can spread considerably further if carried by the river, making it certain – if unchecked – to be more widespread year on year.

Meeting point: Meet at the entrance to the Hogsmill Open Space, just off Knollmead, Surbiton, KT5 9QN. Google map HERE

What to bring: Please wear appropriate clothes and footwear. If it is hot, please bring a hat and suncream. There will be options to work from the bank or in the water in waders. We will provide tea, coffee and biscuits but please bring a bottle of water and a packed lunch.

BOOKING ESSENTIAL – please rsvp using the button below and complete the form to secure your spot. If the event is already fully booked then please sign yourself up to the waiting list and we’ll be in touch if a space becomes available.

Booking for this event will close at 5pm on 23rd June.

The event is one of about 60 taking place during London Rivers Week 2024, which has the theme of London is a river city.

Please email to:

  • Find out more information,
  • Cancel your space if you can no longer make it.

To read our Health and Safety Guidelines for this event please click HERE.

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June 25
10:00 am - 2:00 pm
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Emma, South East Rivers Trust
07741 908 138


Six Acre Meadow
4 Knollmead
London, KT5 9QN United Kingdom
+ Google Map