Delicious Japanese seaweed nori is everywhere today, but that’s not always true. Nori was once called “lucky grass” because the annual harvest depends entirely on luck. Then, during World War II, luck ran out. No nori will grow on the coast of Japan, and the farmers are in trouble. But a breakthrough scientist’s discovery on the other side of the planet revealed something unexpected about the humble plant, turning the unpredictable seed into a stable and plentiful food source.
Nori is most familiar to us when it comes to sushi. It looks unfamiliar when it floats in the ocean, but for centuries, farmers in Japan, China, and Korea have known it by sight. Every year, they plant bamboo poles strung with nets on the beach and wait for the nori to build them up.
At first it will look like thin filaments. Then, with luck, it grows into healthy, harvestable crops with long, green leaves. The farmers did not find seeds or seeds, so no one could plant them. Certain filaments appear throughout the year. That is, they appeared until the Second World War, when pollution, industrial activity on the coast, and a series of hurricanes made the harvest far away. By 1951, nori production in Japan had completely ceased.

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Nori’s secret identity
Fortunately, on an island at the other end of Eurasia, Kathleen Drew-Baker has recently caught fire. He was a lecturer in Botany at the University of Manchester where he studied plants that regenerated using spores instead of flowers. But the university does not accept married women. So when she married fellow student Henry Wright-Baker she was kicked out of the Faculty and resigned to a job as an unpaid research fellow.
Drew-Baker focuses on a type of nori that is not known to everyone: Porphyra umbilicalis. It is a leafy plant that grows on the coast of Wales. Local people harvest it, mix it, and use it to make bread or soup. Known in writing as laver, it is still eaten in Britain but has never had the international status of nori.
Drew-Baker and her husband built a beach lab where she could study her life. During his research, he noticed that he ran across what appeared to be a completely different species, known as Conchocelis. Conchocelis are a group of single-celled organisms that look like pinkish sludge that grow inside abandoned shells. Drew-Baker notes that pink sludge is most common during the summer months, while seaweed shows up during the winter months.
In the end, Drew-Baker found that he was dealing with the exact same plant of a superhero that was not seen at the same time as his alter ego. These seemingly different species were actually the same. They are both types of leaves. In summer, the green leaves send out spores that collect and grow as pink sludge in the shells. In winter, the pink sludge sends out spores that get on the dirt (and bamboo sticks) and built up in the sea again. In 1949, Drew-Baker published a book in Creation explain your presence, “Conchocelis-Phase in the Life-History of Porphyra umbilicalis.”
This might be nothing more than a bit of trivia if it weren’t for the second expert. Back in Japan, Segawa Sokichi at the Shimoda Marine Biological Station read Drew-Baker’s book and found that what was true for Welsh seaweed was also true for Japanese seaweed. The reason no one can find nori seeds is because they are looking for the wrong plant. And nori has stopped growing along the coast due to disruptions to the sea beds full of shells where the pink sludge likes to grow.
Thanks to Drew-Baker’s work, Segawa was able to create a company process that led to stable, predictable production of nori, for which everyone who has a taste for sushi should be grateful.

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Seaweed goes high tech
Today, nori farmers leave nothing to luck. They are still harvesting seaweed from the sea. After that, technology took over. Any spores that grow through the leaf structure of the nori are cut down to a suitable seed length of 0.4mm. To encourage the oysters to grow to the point where they have only one cell, the farmers take these shells from the oysters, string them on a fishing line, and tie them in bottles of water. large that creates a perfect environment for pink flowers to grow.
In the tanks, chlorine is added to the seawater to remove any harmful bacteria. It is filtered with sand to remove dirt. Factory workers regulate the oxygen levels in the tanks and add in regular amounts of magnesium, sodium, iron, and potassium. Even the light levels are controlled. In fact, nori farms only use the bottom shell of oysters because they are softer and allow for more control over the level of light the Conchocelis spores are exposed to.
While the spores grow, some biological engineering continues. Each new batch of spores brought from the sea is examined, cultured, and stored. Its production rate and the conditions under which it thrives are noted. As a result, researchers have identified spores that produce algae in water of different salinity levels, and temperatures. With global temperatures rising, knowing which spores can survive well in warm water will be handy sooner rather than later.
Nori tanks also use temperature to induce Conchocelis to move to the next stage of its life. The water is stored in sub-tropical layers until it is time to harvest the spores that will produce the seaweed. Then equipment drops the temperature in the tanks to shock Conchocelis into action.
An agitator encourages the release of the second set of spores and gets them moving around the tanks. Most of the applications have a state of confusion of time to minute. Then workers put them in tanks for “seeding.” The nets are rolled onto human-sized spools to be sent to farms or stored in freezers until they are needed. At every stage they are checking for quality and concentration of spores on them. People don’t need to put bamboo sticks in the ocean and hope for luck.
Drew-Baker’s discovery was the first step toward the production of a seemingly impossible method of agriculture. Segawa and countless later founders in Japan turned an unpredictable crop into a sure harvest. The application of technology to agriculture, especially this type of agriculture, has completely changed the game. Even the people involved in nori production have changed. While many types of fishing and farming are losing workers, nori farming continues to attract young, skilled people. Seventy years after the agricultural industry seemed doomed, it is thriving more than ever.
Thanks to his many discoveries, Drew-Baker’s career flourished, too. Although she was dismissed for being married, she became the first elected president of the British Human Rights Association in 1952. Today, Drew-Baker is known in Japan as “mother of the sea,” and every year a festival is held in his honor in Uto City.