Shin Joon Hwan, an ecologist, walked last week along a road lined with cherry trees about to bloom, studying the fine hairs around their dark red buds.
The flowers in Gyeongju, South Korea, an ancient capital, belong to a common Japanese variety called the Yoshino or Tokyo cherry. Mr Shin’s advocacy group wants to replace these trees with a species it claims is native to South Korea, the so-called king cherry.
“These are Japanese trees growing here, in the land of our ancestors,” said 67-year-old Mr. Shin, former director of South Korea’s National Arboretum.
Mr. Shin’s nascent project, with several dozen members, is the latest in a complex debate over the origins of South Korea’s cherry trees. The science is intertwined with more than a century of nationalist propaganda and genetic evolution.
Cherry blossoms, celebrated by poets as symbols of transience, hold an important place in Japanese culture. In the Middle Ages, they were associated with elite warriors, the “flower among flowers,” says Emiko Ohnuki-Tierney, an anthropologist who has written about the cherry tree.
During the Edo period, which began in the 17th century, the blossoms were nationalized as a symbol of Japanese identity, she said. And propagandists in Japan’s 20th century military government compared dead soldiers to falling cherry leaves and said they had died after a “short but beautiful life.”
During Japan’s rule over the Korean Peninsula, from 1910 to 1945, Yoshinos were planted as part of an effort to bring “cultural sophistication” to colonial subjects, says David Fedman, the author of “Seeds of Control,” a 2020 book about Japanese forestry in colonial Korea.
Yoshinos have since been intertwined with the thorny politics of colonialism. South Koreans have occasionally cut them down in protest. And some argue that Yoshinos, which Japanese officials also sent to the United States in the early 20th century, should be replaced with king cherries – distinguished by the lack of hair on the tops – claiming the latter are more Korean.
The politics surrounding cherry trees have ebbed and flowed along with Japanese-Korean relations, and nationalist claims about them have largely displaced scientific nuances, says Professor Fedman, who teaches history at the University of California, Irvine.
“Even genetics looks complicated and doesn’t give us the easy answers we’re looking for,” he said.
Mr. Shin’s project is a response to decisions made by Japanese authorities more than a century ago.
In the early 20th century, Japanese scientists described king cherries, found on Jeju Island, south of the Korean Peninsula, as the parent of the Yoshino. The claim that Yoshinos originated in Jeju subsequently motivated South Koreans to spread them throughout the country in the 1960s.
Scientists have since debunked that theory. But another example – that king cherries are Korean – lives on.
The theory has its own critics.
Wybe Kuitert, a retired professor of environmental studies at Seoul National University, said “queen cherry” refers to a range of hybrids, not a species with a geographically defined habitat. He characterized Korean scientists’ attempts to pinpoint a “correct” or original king cherry species as misleading.
“In such a mess of hybrids, what’s the right one?” he said. ‘You do not know. You can’t decide it based on genomic sequences or DNA sampling.”
But Seung-Chul Kim, an American plant taxonomist at Sungkyunkwan University in South Korea whose cherry research has been partially funded by the government, said the initiative to replace Yoshinos was worth it. Even though the evolutionary trajectory of king cherries is unclear, he said, they evolved independently on Jeju.
Only about 200 king cherries grow naturally in South Korea, Mr. Shin said. His group aims to replace all the Yoshinos in the country by 2050, when they are nearing the end of their roughly 60-year lifespan.
“Ultimately, I would like to see Yoshino cherries disappear,” said Jin-Oh Hyun, the group’s secretary general, a botanist who propagates king cherries in the central city of Jecheon. “But we need to replace them in phases, starting in the areas that are most meaningful.”
In 2022, the group surveyed the cherry trees along a promenade near the National Assembly in Seoul, which is heavily visited each cherry blossom season. And last year it studied cherries in the southeastern port district of Jinhae, where a festival is held every spring in honor of Yi Sun-shin, a Korean admiral who helped repel a Japanese invasion in the 16th century.
The trees found at both sites were mainly Yoshino’s.
When Mr Shin surveyed cherry trees in Gyeongju last week, the landscape consisted of pines, bamboo, violets, plums and a 400-year-old zelkova tree. But the cherries, which had not yet blossomed, consumed him.
“It would be great if people around the world could enjoy both Korean and Japanese trees,” he said, adding that the distinction was not widely known. “But things are one-sided now.”
Two arborists in Japan said they respected South Korean efforts to replace Yoshinos.
“Cherry trees alone have no meaning,” said Nobuyuki Asada, secretary general of the Japan Cherry Blossom Association. “That depends on how people choose to view and manage them.”