Photos from Fairbanks show delicate “hair ice” forming on dead wood during an extended snow-free cold spell. Researchers link the phenomenon to the fungus Exidiopsis effusa, which enables hairlike ice strands to grow in humid, slightly subfreezing conditions.

Butternut canker, a fast‑spreading fungal disease with no known cure, has been detected in multiple locations on Prince Edward Island; Islanders are urged to take precautions to limit spread.