How a plant saved a Japanese island

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.

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. 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. 

BBC