Porphyra columbina. Karengo
Previous names
Laminaria spp.
Māori names
Common names
Food
Seaweed dried, packed in baskets for use. Sometimes taken inland as gift exchange. Steamed with other seaweeds, mixed with tutu juice, as an "excellent kind of blancmange-like summer food" (Colenso 1880, 1868a, 1869b).
Karengo grew on flat, clayey tidal rocks. Great quantities gathered round East Cape. Very slippery to touch. Left in sun to dry, stored in baskets. (Makereti 1938)
Welsh `laver" and Japanese `amanori" are related species used for food. Fronds are gathered in winter when they are a foot long, dark and tender, and are dried to be served as a condiment on special occasions ( Moore & Adams 1963).
Medicinal
Karengo fermented with tutu juice and used as a mild laxative. (Goldie 1904).
Brooker, Cambie and Cooper 1987 report that quantities of the plant were gathered and sent to the Māori Battalion in the Middle East during World War II, presumably for its laxative effect. Porphyra species are widely used in other countries for food and medicinal purposes.
See Riley 1994 for information on medicinal uses of related plants elsewhere in the world.