Almost half a century ago, a Japanese horticulturist initiated an effort to rebuild a deforested mountain in the Philippines.

It was in the early 1970s and Osamu Nakagaki was only 25 when he invited his friends and volunteers to eat as many mangoes as they could so he could gather the seeds he needed for planting in San Fernando City in La Union.

Nakagaki was then serving as a volunteer of Japan Overseas Volunteer Cooperation (JOVC), an affiliate of Japan International Cooperation Agency (JICA), according to Inquirer.net.

“In April and May, I would eat ripe mangoes, then planted the seeds which were ready for replanting in December,” Nakagaki said.

Nakagaki and his group consumed around 2,000 mangoes and were able to generate the seeds for their planned mango orchard.

A couple of decades later, the local government of San Fernando would establish a botanical garden where his mango orchard is located.

While Nakagaki would later serve as JICA’s country director later in his career, he was first involved in a project to raise crops during rainy months in the Philippines.

However, he shifted from planting crops to reforestation after discovering the balding mountains of La Union during his many travels in the province.

“I learned that people were practicing ‘kaingin’ (slash-and-burn),” said Nakagaki, who is now 71 years old. “They burned the trees to plant crops, but they were destroying the forests in the process. I came up with the idea of a forest conservation project and told (then) Governor (Juvenal) Guerrero about it, and he was receptive.”

For his project, he chose Kadaclan, a small village in the province which is just 8 kilometers (5 miles) from the city center but only accessible by a trail.

“From the foot of the mountain to the site, we had to walk for two hours,” he recalled.

Nakagaki observed that “residents seemed not to care about forest trees and tended to cut them down. But they didn’t destroy fruit trees.”

He then figured that planting mangoes would be the most ideal to plant to keep them from being cut.

“They waited until the trees grew and bore fruits which they could eat or sell. But before we could plant, we had to eat mangoes to have seeds,” he said.

He started the mango planting project in 1972, just two years after his arrival in La Union. After leaving the country in 1974, other JOVC volunteers continued and expanded his project, with the mango trees covering about 20 hectares of the area.

Nakagaki would later revisit La Union multiple times to check on his project. In 2002, as JICA’s country director, he found that his orchard has grown into a forest filled with fruit-bearing trees. He also returned in 2014 and helped plant guyabano (soursop) seedlings in the area.

Nakagaki’s most recent trip was earlier this month when he brought his son, Naruhito, and some of his friends.

In recognition of Nakagaki’s and his volunteers’ contribution to the area, the place where the garden is located was named “Sitio Hapon”.