Kelp
Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera.
Aquaculture of giant kelp
At the beginning of the 20th century California kelp beds were harvested for their potash. Commercial interest increased during the 1970s and the 1980s due to the production of alginates, and also for biomass production for animal feed due to the energy crisis. However commercial production for "M. pyrifera" never became a reality. With the end of the energy crisis and the decline in alginate prices, research into farming "Macrocystis" declined.