KAHANAHAIKI — The haha tree is extinct in the wild, yet here it is standing right in front of me.

It’s about 10 feet tall with a slender trunk, ruffled green leaves and a checkerboard of circular scars near the top where branches once grew. It’s summer now, so the sweet curved flowers that co-evolved with the beak of Hawaiian honeycreeper birds have come and gone for the year.

The only full-grown haha trees — scientific name Cyanea superba ssp. superba — alive in the forest today were born in a lab. When the last wild surviving plants died almost a decade ago, they were carried out of the forest, underwent autopsies and stripped of their seeds, said Army Environmental Outreach Specialist Candace Russo, who showed me haha on a recent tour of Kahanahaiki Gulch above Makua Valley on the North Shore of Oahu.

Years after they were nearly wiped out, the haha are thriving in Kahanahaiki thanks to a new pilot program to protect them from rats known to eat the plant’s fruit, returning to a single tree multiple times in a season to feast on each fruit as it ripens. Every one of the hundreds of trees alive today can be traced back to some combination of the five “founders.”

The haha is one success story of the Oahu Army Natural Resources Program, a big part of the Army’s $6 million-per-year effort to protect more than 80 different endangered species on Oahu. Because the island has no national parks, it is the Army that serves as the avenue for federal funding to save species.

“This is a side of the Army that people don’t see,” said Loran Doane, a spokesman for U.S. Army Garrison-Hawaii, during the Kahanahaiki tour.

The efforts may not completely counterbalance the various weapons training exercises and other programs the Army has implemented in Hawaii, but it goes a long way toward satisfying the Endangered Species Act requirements that landowners like the Army take steps to protect threatened plants and animals.

Asked why it is important to preserve the native species, Russo said forests provide humans with healthy drinking water — a process that requires a “concert” of plants working together.

“To have the forest function for you, it has to be diverse. All the players have to be there to work properly,” she said. Invasive species undermine that diversity because they are able to “outcompete the natives for all the things that plants need — sun, water, nutrients and space,” creating one-plant forests that might look green but are not healthy.

Superba trees are not the only species to get this special care from the Army. The Natural Resources Program’s Wahiawa baseyard near Wheeler Airfield contains a refrigerator-like incubator with numerous seedlings inside.

Up at Kahanahaiki, a greenhouse contains dozens of sprouting rare plants that could someday soon be replanted in the forest. These replantings, combined with efforts to control rodent populations and clear invasive plant species, could help native species make a comeback in this small corner of Oahu.