Finnish municipalities offer nearly €300,000 in rewards for removing invasive species this summer

Finnish residents can earn cash rewards by removing invasive plant and animal species this summer, with over 90 municipalities participating in a crowdsourced eradication program, Yle reports.

A total of approximately €290,000 in funding—up from last year’s €200,000—has been allocated by municipalities to pay participants who remove species like giant hogweed, Spanish slugs, and the newly targeted rowan-whitebeam through the Crowdsorsa mobile app. The initiative, which combines gamification with environmental work, has expanded significantly, with over 90 municipalities now involved pending confirmation from the Kainuu region.

“Particularly with giant hogweed, we’ve managed to completely eliminate some infestations,” said Toni Salo, CEO of Crowdsorsa, the Tampere-based company behind the app. While lupine removal requires repeated efforts, he noted that smaller areas have been fully cleared, and larger infestations have seen reduced density.

Last year, participants removed invasive plants from over 2.8 million square meters of land and eradicated more than 600 liters of Spanish slugs. This summer, rewards will also be offered for removing rowan-whitebeam, a shrub that spreads aggressively in natural areas.

How the program works

Participants use the app to locate and document infestations, filming the area before and after removal. Submitted videos are reviewed within three days, and approved tasks trigger payments directly to participants’ bank accounts. Giant hogweed, for example, can be retargeted once its icon on the app’s map turns from red to green—typically after two weeks.

In Tampere, where the program launches on May 18, participants can earn rewards for removing giant hogweed and Spanish slugs, with a total budget of €5,240 allocated. Spanish slug tasks require collecting dead slugs in a sealed one-liter container, which is then disposed of in public waste bins. Early in the season, participants earn €4 per liter of slugs; the rate drops to €2 per liter later in the summer.

Five municipalities have discontinued the program due to budget cuts, while Kainuu’s expected participation would add nine more municipalities to the roster.

Target species

The most commonly removed plants include giant hogweed, garden lupine, Canadian goldenrod, rugosa rose, and the newly added rowan-whitebeam. Spanish slugs, which damage gardens and natural ecosystems while spreading disease, remain a key target for eradication efforts.