Botanical atlas

Dead Man's Fingers (also sold as Cheonggak)

Codium fragile

Long before it had a scientific name, coastal foragers from Korea to New England knew Codium fragile by touch alone, its dark, velvety fronds unmistakable among the slippery kelps and wracks of the tide line. In Korea it is known as cheonggak and has been folded into kimchi for generations, prized for the faint crunch and briny minerality it lends to the fermenting cabbage. Along other shores it was gathered simply as a nourishing sea vegetable in lean months, valued more for sustenance than for any specific remedy. Its story is really the story of people learning to read the tide, harvesting what the sea offered rather than what was cultivated by hand.

Safety.

A safe, edible seaweed with no known toxicity, though like other seaweeds it can concentrate iodine, so those with thyroid conditions should eat it in moderation and source it from clean water.