Endangered ‘Aupaka plant brings founder’s family to Hawai’i Island decades later

Descendants of the late scientist, Edward Hosaka, who discovered the endangered ‘Aupaka (Isodendrion hosakae) plant in 1948, visited the Pōhakuloa Training Area to view plants found there on July 17.

During a 2022 survey, only 243 wild ‘Aupaka plants were recorded, making it one of the rarest plants found at Pōhakuloa Training Area. The ‘Aupaka plant was listed as an endangered species in 1991, is endemic to the island of Hawai’i and found nowhere else in the world.

“This was a unique opportunity to showcase what we do to protect endangered, threatened and native plants,” said Pōhakuloa Training Area Commander Lt. Col. Tim Alvarado. “We have a top-notch team of biologists that take care of the plants and educate troops that train at PTA to avoid the areas where these plants are located.”

“We showed them the ‘Aupaka plants propagated in the greenhouse and took them to Pu’u Papapa to view the wild population. Due to ongoing management efforts, natural regeneration is occurring and the ‘Aupaka population is relatively stable,” said Tiana Lackey, a Pōhakuloa Training Area biologist who was part of the Natural Resources team escorting the Hosaka family.

The ‘Aupaka plant is a member of the Violaceae (violet) family and is a small shrub that grows generally about three to six feet tall.

The Pōhakuloa Training Area Natural Resources Program consists of five major program areas that collectively aims to monitor, conserve and improve habitat for endangered, threatened and native species: Botanical, Invasive Plants, Wildlife, Game Management and Ecological Data.

The Natural Resources team monitors and manages native plant species and their habitats, including 20 Endangered Species Act-listed plant species. Some of these plant species at Pōhakuloa Training Area are found nowhere else in the world. Species in the Tier 1 category are those with less than 500 known plants, and Tier 2 have more than 500 known plants.

Pōhakuloa Training Area implements a multi-faceted approach to plant monitoring which includes tracking abundance, identifying emerging threats and investigating specific management needs for each plant.

“My grandfather was a highly regarded scientist and leading authority in the Pacific Rim on grasses and legumes for pasture management,” said Scott Hosaka, grandson of Edward Hosaka.

This is what brought his grandfather to the Big Island as a consultant to Parker and Kahuku ranches in the 1940s. Hosaka graduated from the University of Hawai’i Manoa in 1934 and was employed by the university as an agronomist. He was an avid fisherman and authored a book called, “Sport Fishing in Hawai’i.”

The Hosaka family also visited Hosaka Flats, a fishing site at Pohue Bay named after Edward Hosaka who had a stroke there while fishing with friends and subsequently died in the hospital in 1961. In addition, they visited the University of Hawai’i Mealani Research Station to see a high-yield Kikuyu grass (Pennisetum clandestinum ‘Hosaka’) that Hosaka helped develop.

“The visit was extremely informative and everyone was so warm, welcoming, and generous in their time with us,” said Scott Hosaka. “We were very surprised and impressed the military plays such an important role in the conservation of endangered species in Hawai’i.”