Chondrus crispus
Irish moss
North Atlantic coasts of Europe and North America
Native to North America
WaterHigh
Overview
Chondrus crispus, known as Irish moss or carrageen, is a red seaweed of the North Atlantic rather than a true moss or flowering plant. It grows as a flat, branching frond, or thallus, 2.8-7.9 inches (7-20 cm) long, attached to rock by a small disc-shaped holdfast. The fronds branch repeatedly in a fan-like, forked pattern, with flattened segments that broaden toward rounded, notched tips. Color ranges from dark purplish-red and greenish-brown to nearly black, and the fronds often show a blue-green iridescence underwater. The texture is firm, cartilaginous, and elastic. It lives in the lower intertidal and shallow subtidal zone, anchored to stones and ledges that are exposed at low tide and submerged at high tide. The plant has no roots, stems, leaves, or flowers; it absorbs water and nutrients directly across the thallus surface. Its cell walls are rich in carrageenan, a gelling carbohydrate harvested commercially for use as a thickener in foods and other products. Native to rocky Atlantic coasts of Europe and North America.
Native Range
Native to the rocky Atlantic coasts of northwestern Europe and northeastern North America, from Iceland and Norway south to Portugal, and from Labrador south to New Jersey. It grows on intertidal and shallow subtidal rocks and in tide pools.Suggested Uses
Harvested as a source of carrageenan for use as a gelling and thickening agent in foods, and gathered traditionally for cooking and as a coastal foraged food. It is not used as an ornamental or garden plant.How to Identify
Appearance
Size & Dimensions
Height3" - 8"
Width/Spread2" - 6"
Bloom Information
As a red alga, Chondrus crispus does not flower. It reproduces through an alternation of generations, releasing spores from reproductive patches on the fronds; separate gametophyte and tetrasporophyte plants look alike but differ in their iridescence and reproductive structures. Reproductive fronds are most evident in summer and autumn.
Detailed Descriptions
Foliage Description
purplish-red to greenish-brownGrowing Conditions
Water & Climate
Water Needs