Tackling Himalayan balsam on the Wensum

Summary: 

Norfolk Rivers Trust and the Norfolk Non-Native Species Initiative (NNNSI) have renewed their ambition to reduce, and where possible, eliminate the invasive Himalayan balsam from the Wensum river catchment.

Project description:

Himalayan balsam (Impatiens glandulifera) is an invasive non-native species (INNS) that spreads rapidly along watercourses, out-competing native plants. Its seasonal nature leaves entire stretches of riverbanks bare in winter, increasing vulnerability to erosion and threatening biodiversity.

The second phase of the project builds on the successes of the first (2020 - 2024), where dedicated volunteers helped control balsam across 71,374 m², extending 21,714 m in length. Efforts primarily targeted Wensum tributaries and headwater locations, preventing reinfestation downstream.

The project brings together a diverse network – partner organisations, businesses, community groups, work parties, walkers, anglers, canoe clubs, landowners and farmers – all working together to improve their local river by removing this invasive species.

Project actions and goals:

  • Conduct a re-baseline assessment.
  • Shift focus to downstream locations after multi-year control efforts at upstream sites have significantly depleted the seedbank, resulting in little to no regrowth.
  • Continue to target known balsam hotspots.
  • Develop a data dashboard to enable real-time viewing of balsam sightings and control work.

Partners and funders:

This project is delivered in partnership with Norfolk Non-Native Species Initiative (NNNSI), with funding from Anglian Water WINEP.

What you can do:

Himalayan balsam can be manually controlled, allowing for quick progress – and it’s surprisingly satisfying! Join one of our practical conservation action days to help uproot and remove balsam plants.

Get involved by signing up with a local volunteer group (email NNNSI@norfolk.gov.uk or volunteering@norfolkriverstrust.org).

You can also support the project by reporting recent sightings and completed control work. Simply use the following survey forms, accessible via web browser or mobile phone:

Report recent sightings here

Report recent control work here

Alternatively, email NNNSI@norfolk.gov.uk (please include a date, location and photo, along with any other additional information such as abundance or size of infestation)

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