Keltalammikki VEX Project
Keltalammikki VEX – Yellow fringed lily termination and management in the Aura River
1.11.2025–31.10.2027
Funders: Economic Development Center, Ossi and Raija Tuuliainen Foundation, Aura River Foundation’s own funding
Toiminta-alue: The concrete management measures are implemented in the Aura River in the municipality of Lieto. Project communication, monitoring results and developed operational models serve the entire Aura River catchment area and its municipalities, including Turku, Kaarina and other stakeholders along the river.
Project description
The Keltalammikki VEX project focuses on stopping the spread of yellow fringed lily (Nymphoides peltata)in the Aura River. Yellow fringed lily is a rapidly spreading invasive aquatic plant that forms dense floating mats, reduces water flow and displaces native aquatic vegetation.
Although yellow fringed lily has not yet been officially classified as a harmful invasive species in Finland, its local impacts in the Aura River are already significant. Without prompt management measures, the plant may spread uncontrollably and negatively affect both the ecological status of the river and its recreational use.
The project pilots a surface covering method, which has been successfully used in Sweden but has not previously been applied in flowing waters in Finland. The aim is to develop an effective, environmentally friendly and scalable management model that can also be applied in other water bodies.
Project news
The Keltalammikki-VEX Project Seeks Solution to Control the Spread of Yellow Fringed Lily in the Aura River Using Floating Covers
Aurajoki Foundation is launching a two-year project to develop a…
Read more >Project objectives
The objectives of the Keltalammikki VEX project are to:
- stop the spread of yellow fringed lily in the Aura River
- pilot and develop the surface covering method for flowing waters
- produce practical management practices for municipalities and authorities
- increase awareness of yellow fringed lily and its impacts
- engage citizens in the protection and monitoring of aquatic environments
Management method: surface covering
The project develops a surface covering method in which yellow fringed lily stands are covered with air-permeable fabrics attached to lightweight frames. The covering blocks light from reaching the plant, causing it to weaken and die in place.
The advantages of the method include:
- low risk of spreading the plant during management activities
- easy monitoring, for example by canoe
- the possibility to repair and maintain the structures during the growing season
The functionality and impacts of the coverings are monitored in cooperation between volunteers and experts.
Monitoring and documentation
The project monitors:
- the technical performance and condition of the coverings
- the development of yellow fringed lily stands and possible regrowth
- the impacts of management actions on aquatic vegetation
Monitoring is carried out using drone imagery, GPS and QGIS mapping, as well as observations by volunteers. The results are documented and published on the project website and compiled into a final report.
Communication and participation
Open communication is a key element of the project. Effective management of yellow fringed lily requires that information on plant identification and prevention of spread reaches riverbank residents and recreational users.
The project includes:
- communication on yellow fringed lily and its management via the website and social media
- reporting on project progress to municipalities and stakeholder groups
- guidance on how individuals can help prevent the spread of the plant
Implementation and partners
Lead organisation: Aura River Foundation
Partners include municipalities along the Aura River, the Economic Development Center, expert organisations, local associations and volunteers. International cooperation is carried out with the municipality of Tingsryd in Sweden.
Contact information and further details
Eelin Hoffström-Cagiran, CEO Aura River foundation
eelin.hoffstrom-cagiran@aurajoki.net
More information on invasive species: vieraslajit.fi