The tree was taken in September from David Fukumoto's nursery in the Big Island community of Mountain View, he said.
Fukumoto began growing the tree in 1962 to spruce up the bare-bones Honolulu apartment he and his wife lived in as newlyweds, he said Tuesday.
"I ended up getting hooked on growing bonsai," Fukumoto, 78, said, describing how he took it with him when he moved to the Big Island where he runs a nursery called Fuku-Bonsai. "I feel as if they kidnapped my daughter. This is my first bonsai."
Fukumoto said the tree was on higher ground when 3-feet-high flooding from Hurricane Lane wiped out some of his other bonsai trees in August.
Police don't want to reveal the tree's value, Capt. Ken Quiocho said. Police started asking the public for help Tuesday because they have exhausted leads, he said.
"We desperately want to try to find this tree and get it back to the owner," he said.
Police believe the person who took it was familiar with the tree and knew its value, Quiocho said.
"It's 56 years old," Fukumoto said. "How can you put a value on that?"
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