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Starry Stonewort

Common Name: Starry Stonewort
Scientific Name: Nitellopsis obtusa
Origin: Europe and Western Asia


Starry stonewort is a rooted macroalgae often found in lakes and rivers and can grow to two meters in length.  This plant is green with star shaped rhizoids that form from late fall though winter.


This invader can live in fresh or brackish water and can tolerate low light and nutrient levels as well as high salinity conditions. They are often found 3 to 20 feet deep in lakes and slow-moving rivers.


An invasion of starry stonewort can form a mat on lake and river bottoms, outcompeting other native species and destroying habitats. They are also the preferred substrate for zebra mussel attachment, magnifying the presence of invaders.


Manual removal of starry stonewort is difficult as is causes the spread of rhizoids and is impractical on a large scale. Copper-based herbicide application is likely the most effective control method.

Distribution: View Map

SSW FAQ – Nitellopsis Working Group