About 450 residents of this tsunami-ravaged town kicked off an experiment Monday to turn a 50-meter-long mound of disaster debris into a new forest by planting 3,000 saplings on it.

The idea is the brainchild of bionomics expert Akira Miyawaki, professor emeritus of Yokohama National University, who was searching for a good way to make use of debris from the March 2011 earthquake and tsunami without damaging the environment.

The participants, which included Environment Minister Goshi Hosono, planted 16 different kinds of trees on the 4-meter-high dirt mound, which is composed of pieces of concrete and wood washed away by the powerful tsunami.

The trees will be about 10 meters high in decade or so, according to Yokohama Rubber Co., which organized the event and has worked with Miyawaki before on similar projects.

Otsuchi resident Yoko Abeyama, 63, said she was happy to participate in the experiment, which is apparently the first to use disaster debris as part of ecological efforts in Japan.

"The debris was becoming a nuisance for us, so it's nice to see it finally utilized. And the fact that these trees will grow up will be something we can look forward to," she said.

The central government is planning to build more than 140 km of tidal-wave prevention forests along parts of the coastline between Aomori and Chiba prefectures from June. Hosono said he will think about using this method again when the project begins.