| Scientific Name |
(Nitellopsis obtuse) |
| Classification and Permitting Level |
1 - Prohibited Aquatic Nuisance Species |
| Species Description |
Starry stonewort is a nonnative macro-alga that can blanket lake bottoms and grow nearly two meters high. The species can easily be identified by its white, star-shaped bulbils, which are asexual reproductive structures. |
| Preferred Habitat |
Optimal water temperatures are from 0 to 24 degrees Celsius. Starry stonewort is typically found in the littoral zone but may be up to 8 meters deep in some waters. |
| Reason for ANS Designation |
Starry stonewort can easily be moved by recreational watercraft and equipment. Once established, the algae can proliferate, impede recreation, destroy benthic habitat, and outcompete native aquatic plants. |
| Place of Origin |
Native range stretches from Western Europe to Japan and was likely introduced to the United States in 1978 through ship ballast release. |
| Stopping the Spread |
When taking equipment out of a lake or stream, inspect it to ensure there is no aquatic vegetation. Leave any aquatic vegetation you find at the lake from which it was taken. Wash the outside watercraft with 140-degree water for 10 seconds of contact time to reduce the risk of incidental spread. |
| Additional Information |
USGS Fact Sheet |
