Instead of sleeping in, Cole Nakao sacrificed a few more hours of shut-eye Saturday to chop up the invasive hau trees that blanket Kawainui Marsh.

Using the sleeve of his Hawaiian Electric Co. volunteer shirt to wipe sweat from his face, the 17-year-old Mid-Pacific Institute student said, "I just wanted to come out with my mom and help the community."

Nakao was one of 120 volunteers from HECO and the Kailua Hawaiian Civic Club who participated Saturday in a cleanup of Ulupo Heiau and Kawainui Marsh behind the Kailua YMCA.

"We’re very fortunate to have community-minded people with such a strong volunteer spirit," said Janeen Miller, senior communications specialist for HECO.

The day started off with Hawaiian oli, or chant, and a narrative history of the land by Chuck "Doc" Burrows, co-curator of the Ulupo Heiau State Historic Site.

"All of them (the volunteers) have come with righteousness to do well, to work well and to malama (care for) the site," Burrows said.

The 100 HECO volunteers — HECO employees and their families — joined the 20 members from the Kailua Hawaiian Civic Club in its monthly community service project to beautify and restore the historic site. The Kailua Hawaii Civic Club is a nonprofit organization dedicated to the preservation and enhancement of native ecosystems and the Hawaiian culture, its website says.

While HECO coordinates community service events at least once a month, this was the first one at the Kailua site.

"We have so many culturally strong people, so we try to vary the areas we go to," Miller said. "We’re just trying to touch everything known to Oahu."

From 8 a.m. to noon volunteers cleared invasive plants and tree trimmings and planted native plants in an effort to help restore the native wetland bird habitat.

"We don’t have the money to maintain the site, so we want people to come down and help," Burrows said.

Allison Tai, 32, said it’s refreshing to be outside of the office working with her co-workers.

"There’s a lot of work to do in the community, so everyone needs to chip in," said Tai, administrative assistant for HECO’s power supply engineering division.

Spanning nearly 1,000 acres, Kawainui Marsh is the largest remaining emergent wetland in Hawaii, said Burrows, head of ‘Ahahui Malama i ka Lokahi and board member of the Kailua Hawaiian Civic Club. It provides a primary habitat for four of Hawaii’s endemic and endangered water birds: the aeo, alae keokeo, alae ula and koloa. The marsh is also home to several taro patches.

Surrounding the Kawainui Marsh are three heiau, or sacred temples: Ulupo, Pahukini and Holomakani.

Angie Eide, 45, who works in HECO’s demand and response division, said it was great that Burrows was present to explain the history of the site to the volunteers.

"Doc Burrows brings his cultural knowledge and that’s important as we try to preserve the natural land," Eide said.

With HECO approaching its 120th anniversary in October, Miller said there isn’t a better time to serve the community.

"This is all our home and we need to continue to do good for our home," she said.