The algark stalk was a species of carnivorous fungus that was native to the world of Gamorr.

Algark colonies grew on high stalks, whose tops formed a wind-sensitive sail-bulb that would dispense spores if agitated by the wind or a passing creature. The spores would take root in both soil and animal flesh, growing and forming a new colony. Any animal that the spores grew upon would eventually be consumed by the fungus, but not before the new colony had been transported miles from its parent.