Mat Kubo spent three weeks living off the land in urban Honolulu.

He ate only food grown, caught or found in his environment; he moved mostly by his own personal effort. His main meals were fruit he requested permission to pick, traded for items from his own yard.

He hunted and fished. To lighten his carbon footprint, Kubo rode his bike from Kaimuki to Kalihi — or if he were going farther afield, he caught a ride with a friend.

Kubo got hungry and sunburned and dropped a few pants sizes. But he also met people who lent him a hand and supported his experiment.

He turned the results of his efforts into a gallery installation, now on view in Chinatown at The ARTS at Marks Garage. His piece is called "ActionFunUrbanSurvivalism," part of a group show called "Eco/Logic."

The multimedia piece serves as a road map, both literally and figuratively, of the 21 days he lived off the land. One component: his bike, fitted to carry a telescoping mango picker.

"I was thinking, what can one person do?" Kubo said.

While community groups raise awareness, he said, "as artists, we can be impatient. Can we make something happen?"

City folks might think the store is the only place to get sustenance, but Kubo strived to prove that a fallacy.

"I started off as a test to see if I could sustain myself by things I gathered in urban Honolulu," he said. "I found there were enough resources here.

"There are so many different ways we can make a sustainable place."

And he was buoyed to find the old ways — living interdependently among neighbors — were still present, and the possibility of urban agriculture not so far-fetched.

Kubo set some boundaries for his experiment. He didn't go completely off the grid.

"I'm not homeless, so no taking handouts or resources from people who really needed it" was one rule, leading him back home for a place to lay his head nightly.

No picking fruit without permission was another.

If something was found on the ground (like that can of Libby's pumpkin in Chinatown, found the first day) or if the owner of the tree was happy to share, those edibles were fair game.

So was a crab he caught out of the Ala Wai. Kubo knows most people would fear Ala Wai fare, but he says he met a fiftysomething fellow crab fisherman who used a chicken leg tied to a stick for bait, then scooped his catch up with a net — and that guy didn't look any worse for his efforts.

"It was a tasty crab," he said. "... Either I shaved some time off my life, or I'm impervious."

While just about anything tastes delicious on an empty stomach, Kubo said the conversations with people he met along the way and the random acts of kindness he received were even better than the ripened mango and harvested lychee.

But it wasn't just about getting — it was also about giving. If Kubo asked to pick someone's pomelo, for example, he offered them lemon, bay leaves or basil from his own yard.

"It wasn't so much a trade," Kubo said. "I asked if I could pick some fruit, and they said, 'Yeah, sure, go ahead.' ... I'd give them what I had."

These exchanges led to conversations about the project and much encouragement in his efforts.

"It evolved from a sort of hard-core survival thing to more of a deeper, warmer relationship building with people," he said. "It wasn't a test of myself anymore. That kind of became secondary after a while."

Don't underestimate the power of hunger, however. Kubo admitted the first week was "really hard." He lost a lot of weight and muscle mass, pulling up his shirt to show his new belt-loop, two hole-punches over. That might remind some of the starvation diet endured by the naive adventurer in the book and film "Into the Wild."

Days of riding home hungry started to blend together, and at times, Kubo couldn't muster the energy to post pictures of his journey on his daily blog, an integral part of the project for him. He grew sore, tired and depressed.

The heat of the drumming sun began to get to him. The drop in caloric intake, the blurring of his mental acuity took its toll and he started to think, perhaps, "this was the worst idea I ever had."

But somehow he powered through, knowing the suffering was all for his art. And that breakfast bowl of granola with goji berries, walnuts and almonds the day after the project was finished made him one happy man.

Asked to share the lessons he gleaned from his adventure, Kubo talked about the importance of neighborhoods, where people were more welcoming not only to him but to his project.

A man gave Kubo delicious lychee off his beautifully pruned tree in Palolo. A fisherman and his wife shared their catch after seeing Kubo spend seven unproductive hours with a pole.

"It sounds cheesy, but I learned you get what you give. The more you give of yourself, your outlook on life changes, and is much more positive," he said.

The experiment also changed his outlook on his art.

"Being an artist here is really isolating. (There are times when it's) gotten me down, made me want to quit. This project brought me back (to how I) need to rebuild, foster relationships with people. It wasn't so much about feeding the body, which was important, but feeding the soul."