Rockweed may refer to: Ascophyllum nodosum, a seaweed also known as knotted wrack or Norwegian kelp Fucus distichus, found in tide pools in the Northern Hemisphere Fucus gardneri, a similar seaweed also known as bladderwrack Fucus vesiculosus, a similar seaweed also known as bladderwrack Pilea microphylla, a vascular plant native to Florida Silvetia, a common brown seaweed of Pacific Ocean rocky seashores