For centuries, residents on a far-flung Japanese island have survived hardships by consuming a highly toxic plant. Now, this deadly delicacy is at risk of dying off.

Eiko Kawauchi walks with a cane in one hand and an axe in the other. At 79, she may not move as quickly as she used to, but once she’s taken a seat, she can still swing an axe with the vigour of a woman half her age. 

Moist-looking wood chips soon fly as Kawauchi hacks away at the trunk of a cycad tree, or sotetsu as it’s known here in Japan. She’s trying to get past its diamond-patterned flesh to the core, just as her grandparents taught her many years ago.

In almost every other part of the country, people avoid having anything to do with these highly toxic trees; when eaten raw, cycads can cause internal bleeding, liver damage and even death. But on Japan’s far-flung Amami Oshima island, located some 300km between the tip of Japan’s south-western-most main island, Kyushu, and Okinawa, things have historically been quite different.

Part of the Ryukyu Islands and lying closer to Taiwan than Tokyo, Amami Oshima is tropical enough that cycads thrive. Often mistaken for palms because of their stout, cylindrical trunks and long, fan-like leaves, cycads have been around for the past 280 million years and are considered to be living fossils. In fact, these fern-shaped fronds were so abundant during the Jurassic Period that the era is often called “The Age of Cycads”. And while dinosaurs had no problem digesting the neurotoxin found in cycads, it remains deadly to humans.

 

But for the 67,000 residents of Amami Oshima, cycads have served both as staple and a source of survival in dire times. Over the centuries, the islanders have quietly developed a way to harvest these toxic trees and remove the poison through a labour-intensive, four-week process. They start by cutting the pith from the trunk, grinding it into a flour and then washing and drying it vigorously and repeatedly to leach out the natural toxins. This combination eventually yields an edible sago starch known as nari, which can be used to make noodles or added to rice. 

“It’s hard work, yes,” said Toshie Fukunaga, watching Kawauchi wield the axe. Along with two friends also in their late 70s, Fukunaga and Kawauchi are among the last people on the island who still know how to safely process the cycads.

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There are just 55 people living in their coastal village of Ikegachi, which is nestled on a turquoise bay. Cycads grow naturally at the border of the settlement, and more still are planted in allotments. Like many parts of Japan, Ikegachi has an ageing population and the majority of young people don’t just leave the village but Amami Oshima island, too. Most either head to the prefectural capital of Kagoshima City on Kyushu island, or further north to one of Japan’s mega cities in search of work.

We’re too old to teach people now

They say you’re never too old to learn, but according to these pensioners, you can be too old to teach, as the effort required to teach the detailed process would outweigh the benefit. Kenshi Fukunaga is 25 and the only young person still living in Ikegachi. “I’ve tried to learn how to work with the sotetsu,” he explained, “but it’s not so easy.”

“And we’re too old to teach people now,” his grandmother, Toshie, conceded.

The day before visiting this village, I’d spent time in the Amami Museum, an hour’s drive north of Ikegachi in the island’s main city of Amami, also known as Naze. There, I’d spoken with museum official Nobuhiro Hisashi, who explained some of the history and importance of the plants on the island.

He said that in the past, cycads were eaten at times of desperation. During the feudal Edo Period (1603-1868), Amami Oshima was under the domain of the Satsuma clan, whose territory more or less corresponded to Japan’s southern Kagoshima prefecture today. The island was often lashed by typhoons and struggled to grow traditional crops, but because of its tropical latitude, it was one of the few regions in the country that could grow sugar. 

“The Satsuma clan would only send rice allocations in exchange for brown sugar,” Hisashi explained. “If that crop failed, the people of Amami Oshima would starve. So, in the bad years, cycads had to be eaten.”

While there is no known evidence showing how people first learned how to safely consume cycads, Hisashi’s best guess is that it was trial and deadly error. Now though, the museum is keen to document the harvesting process, in case the last of the poison processors never take on any apprentices. 

Though the Satsuma rulers’ tyranny was eventually removed at the end of the Edo Period in 1868, during World Wars One and Two, the islanders’ ancient cycad knowledge again came to the rescue. Faced with severed supply lines from the main Japanese islands and at risk of starvation, the islanders turned to the cycads once more to survive. “No-one knows exactly how old this practise is,” said Hisashi, “but it has been very important to our island. Now we try to produce books so people do not forget.”

Given the cycad’s remarkable history and importance to the island, it’s surprising that much of the Ikegachi community seems reasonably content to let the tradition die off. Elders here would have eaten the sotetsu as part of a limited, post-World War Two diet. Some people from that generation still refer to this time as “sotetsu jigoku”, or “cycad hell”. I asked if that’s why they’re not trying to protect it. Are the associated memories too traumatic?

“No,” replied Fukunaga quickly, “Those memories are all happy. We were young then. I remember the taste of it very well. We would have all died if there were no sotetsu.”

The truth about the decline of the island’s potentially deadly diet is a little more pragmatic. Amami Oshima is not as affluent as some of Japan’s other 6,851 islands, but compared to the past, these are times of plenty. With no exploitative samurai to worry about, bountiful, imported produce and an improved understanding of farming methods, few islanders see the value in making the colossal effort needed to safely consume cycads.

Not only is transforming toxic tree trunks into food hard work, but it comes with the risk of running into the habu snake, a type of venomous pit viper endemic to this archipelago. Nonetheless, Kawauchi, Toshie and their two friends still make a few batches a year, and brought along a large pan of nari-enriched rice for me to try.

As I sat in the shade of a blue awning stretched over bamboo stilts, the four women formed a semi-circle around me. Each looked on as Kawauchi dumped a large ladleful of cycad rice topped with some soy-soaked garlic into a styrofoam bowl and passed it to me. Looking at the septuagenarian audience, I was as nervous about my chopstick skills as I was of this dish that could potentially kill me. Before the first mouthful, I quickly asked when was the last time someone fell afoul of the cycads?

“No, no, no! Never, never,” replied Fukunaga, seeming a little indignant.

I quickly ate some of the rice, to placate her as much as anything. The biggest surprise was this infamously toxic, prehistoric plant tasted of almost nothing at all. I downed some more to double check. If anything, it reminded me a little of Japan’s similarly notorious pufferfish or fugu, in that, for all the talk of suffering an agonising death after biting into it, it has a flavour that’s subtle to the point of undetectable. 

“What do you think?” asked Fukunaga. 

While I was wondering how to reply, she answered for me. “Not so much flavour, right?”

It’s perhaps no surprise that cycads aren’t considered a necessary food source on Amami Oshima anymore. Yet, while the ladies of Ikegachi still occasionally go to the trouble to prepare it, there is one island restaurant that keeps the novelty of eating it alive. 

On a peninsula only a few miles from the Amami Airport, there sits a tiny udon restaurant called Mash Yaduri. No-one I met was quite sure of its location, and Hisashi had spoken about it as though it was some sort of myth, but I eventually found it at the end of a narrow beach road.

I arrived around 10:00, hoping to hear about their specialty cycad dishes. While in other parts of the island cycad is spoken about as a thing of the past, here, owner and chef Tae Wada and husband Akiho have been selling noodles made from the starch for the last five years. 

Even with no translator on hand, Wada somehow seemed to know what I had come for, and a couple of minutes later, a bowl of cycad-udon and chicken in a hot umami broth lay in front of me. Truthfully, its flavour was also a little bland, but the rich history now wasn’t lost on me.

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