Invasive floating pennywort confirmed spreading in an Oregon waterway
iNaturalist: d4370
Invasive Species
If you fish, kayak, or garden near a pond in the Willamette Valley, this mat-forming invader can clog waterways and crowd out the native plants your local ecosystem depends on.
Someone spotted a patch of floating marsh pennywort in Corvallis and logged it on iNaturalist, where experts confirmed the identification. This plant isn't native to Oregon and it spreads fast across water surfaces, forming dense mats that block sunlight and choke out other aquatic life. Confirmed sightings like this one help land managers track where the invasion is showing up so they can respond before it takes over.
Key Findings
Observation was verified as 'research-grade' on iNaturalist, meaning the identification is confirmed by community consensus
Species (Hydrocotyle ranunculoides) is a known invasive aquatic plant capable of forming dense floating mats
Location data pinpoints the infestation to Corvallis, Oregon, useful for regional invasive species tracking
chevron_right Technical Summary
A citizen scientist confirmed floating marsh pennywort, an aggressive invasive aquatic plant, growing in Corvallis, Oregon. The sighting matters because this species can choke waterways and outcompete native wetland plants once established.
Abstract Preview
Original paper
floating marsh pennywort (Hydrocotyle ranunculoides) observed in Corvallis, OR, US
Research-grade observation of floating marsh pennywort in Corvallis, OR, US.
open_in_new Read full abstractAbstract copyright held by the original publisher.
Species Mentioned
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Hydrocotyle ranunculoides, commonly known as floating pennywort, or floating marshpennywort, is an aquatic plant in the family Araliaceae. It is native to North and South America.