Long, thick pieces of brownish-green hose have washed up on a steep and rocky beach. As any beachgoer knows, this is bull kelp (Nereocystis luetkeana)–a seaweed that can grow up to 60 feet long. When I was a kid, my friends and I would pretend we were cowboys, using the long “ropes” for lassoes. In Alaska, Native Americans used them as lines for deep sea fishing.
Bull kelp looks very plantlike, but it is actually a brown algae and in an entirely different kingdom. In the deep water where it grows, it anchors itself to the bottom with a root-like “holdfast” while the rest of the plant stretches toward the surface, buoyed by an air-filled pocket that grows at its upper end. Sometimes you’ll find the holdfast still gripping tightly to a rock that has washed up along with the plant. More often, you find the upper part–a rubbery length of stem topped by the bulbous float (which looks a lot like a turkey baster…)
This huge algae is an annual, meaning it grows from a tiny spore and lives its entire life span in only one year. Sometimes it can grow up to 10 inches in a single day! Otters, fish, sea urchins, crabs and other sea creatures live in the long ribbon-like leaves that grow from the top of the plant. You can buy edible bull kelp dried at the health food store or hop in a boat to harvest your own (it’s better fresh than after it’s been uprooted and washed up ashore). The leaves are eaten dried, and once washed and peeled the rubbery stalk can be pickled, or used in relish in the same way as cucumbers or tomatoes.
Flowers Of Marin 