Overview
This observation shows a coarse, dark olive-brown to almost black brown alga. The thallus is stiff and much-branched, reaching up to 2 m (6.5 ft) in height. The branches are cylindrical to slightly flattened and arranged in an irregularly alternate pattern, with sharply pointed spines being a prominent feature. The plant arises from a small, disc-shaped holdfast. Notes: This sample (SM-0024) is from a private collection that will be donated to the Museum of the North Herbarium.
- Type
- Other
- Severity
- MODERATE
- Source
- iNaturalist
Symptoms
Geographic Spread
Treatments
Consult Extension Service
Contact your local cooperative extension service for diagnosis and site-specific treatment recommendations. Accurate identification is essential before treatment.
Recommended Products & Tools
Helpful supplies for managing Witch's hair. Always read and follow label directions, and confirm a diagnosis before treating.
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Frequently Asked Questions
What is Witch's hair?
This observation shows a coarse, dark olive-brown to almost black brown alga. The thallus is stiff and much-branched, reaching up to 2 m (6.5 ft) in height. The branches are cylindrical to slightly flattened and arranged in an irregularly alternate pattern, with sharply pointed spines being a prominent feature. The plant arises from a small, disc-shaped holdfast. Notes: This sample (SM-0024) is from a private collection that will be donated to the Museum of the North Herbarium.
What are the symptoms of Witch's hair?
Where is Witch's hair currently found?
Witch's hair is currently active in Alaska. It has been reported in 1 total state across the United States.
How do I treat Witch's hair?
Treatment options for Witch's hair include: Consult Extension Service. Treatment approaches may include chemical, biological, cultural, and mechanical methods depending on the severity and context.