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Starry stonewort (Nitellopsis obtusa)

Starry stonewort Description: This species is listed on the Michigan prohibited aquatic plant list. Appears in July and increases through October.

Habit: Aquatic macroalga with smooth, irregular branches; rootlike rhizoids. Forms dense mats that cover lake bottoms.

Leaves: Whorls of 5-8 fine, uneven-length branches arise at an acute angle from nodes. Contents can be squeezed out of tube-like cell wall when cut; dark reddish gametangia.

Stems: May reach 80 cm (33 in) in length.

Flowers: Lacks true flowers. Cream colored bulbs form at the base of each cluster of branches.

Habitat: Native to Europe and Asia. Found in still or slow moving waters; grows at depths ranging from 1 m (39 in) to 30 m (~93 ft).

Reproduction: Probably introduced in ballast water. Dispersed by boats, waterfowl.

Similar species: Common stonewort (Chara vulgaris), which feels brittle and scaly, unlike the starry stonewort.

Monitoring and rapid response: Algaecides and mechanical harvesting.

Credits: The information provided in this factsheet was gathered from the Michigan Lake Info and the Michigan Natural Features Inventory.

Individual species images that appear with a number in a black box are courtesy of the network ( photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (

Common Name:

Starry stonewort

Scientific Name:

Nitellopsis obtusa







USDA Symbol:


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