18/05/2026
Well, this would beat pulling them up by hand! Loads of our groups have been helping control this invasive species in our local area lately - a well researched biological control would be just the ticket👌🏾
School of African Cultures -soac
RSPB Lochwinnoch Nature Reserve
RAMH
Ren CAN - Renfrewshire Climate Action Network
Great to see rust spores growing on the stem of a Himalayan balsam plant on one of our test sites in the region. Himalayan balsam is one of the non-native invasive plant species that we’re trying to control across the catchment. It forms dense monocultures that reduce biodiversity, cause riverbank erosion and increase the chance of flooding.
For the past few years, we’ve been trialling a biological control technique which releases a
co-evolved rust pathogen that exclusively attacks Himalayan balsam plants, reducing their vigour and seed production whilst leaving the indigenous species intact. It is hoped this will help restore affected riverbanks and native habitats over time.
The rust fungus is a natural enemy of Himalayan balsam, is highly specific to this particular plant, and has undergone extensive testing against over 74 species including crops and closely-related UK-native plants to make sure that it doesn’t attack other species. It has been approved for release by DEFRA.
Once established, it is hoped that the rust fungus will become self-sustaining, controlling the Himalayan balsam population in a way that is reliable, cheap and environmentally benign.
The trial is being led by CABI and delivered through the LIFE WADER and Destination Tweed projects.
LIFE WADER Destination Tweed UK
