Restore 100 Hectares of the Miyagi Coastal Forest

The beginning of June, Dendrolimus spectabilis, which only consumes pine, had abnormally occurred, and we were busy dealing with the issue. There were lots of confirms in occuring of another caterpillar, some caterpillars had poison. Our staff and volunteers who related to work were stung by poisonous hair, and they received damage such as; an itching sensation in their arms and neck. Although Dendrolimus spectabilis doesn’t have personal damage, they ordinally consume pine leaves so if we keep letting loose them, pine’s leaves would disappear in an instant. It’s obvious that the result of decline of photosynthetic rate, stopping tree height stretch, the trunk not becoming thick, and decreasing root’s growth. In order to grow strong coastal forest, it’s really necessary to exterminate above caterpillars.

By getting the cooperation of 182 volunteers in total, we executed caterpillar extermination by spraying in 1.75ha (equivalent to 5,775 Japanese black pines) of the most damaging area in our project on three days from 13 to 15 in June. We estimated that we could exterminate more than 30,000 caterpillars. Next week, the pesticide was sprayed by power sprayer by the cooperation of all people from the organization of the Natori-shi shore forest reproduction (Natori-shi kaiganrin saisei no kai) who are in charge of making plants. Contrary to this fact, We could check that caterpillars have spread over a span of approximately 23 ha north of 100 ha in after survey, hence we decided to execute aerial chemical spraying by helicopter on June 26th.

On that day, 2 aerial work platforms to carry operators who control 2 helicopters, 2 tracks which load equipment and chemicals and 9 expert staff were gathered at 4am. The reason why we start work in the early morning, if it is a morning when the wind is light the risk of the chemical scattering out of the forest would be decreased. 30L chemicals were sprayed per 1 ha. Different from drones, the helicopter’s chemical carrying capacity is a lot and can work efficiently,therefore spraying to approximately 32ha forests and withdrawal of all equipment finished at 8am.

Toshimichi Yoshida who is in charge of this project mentioned that “Though I thought that the time will come that aerial chemical spraying by helicopter would be demand to suppress the damage from Dendrolimus spectabilis one of these days, I didn’t expect that we’ll be flying helicopters to exterminate caterpillars.”, and he appreciate that “Thank to all of you who support us, we were able to decide quickly.” We’ll patrol 100ha’s pine forest regularly, not to miss small abnormalities, and deal with it immediately if there are some factors to avoid pine’s improvement and we would like to grow strong coastal forest. Thank you for your continued support.

It has been the 14^th year since the Coastal Forest Restauration Project was launched on the coastal area of Natori City, Miyagi Prefecture, following the Great East Japan Earthquake which caused devastting damage in March 11, 2011.

Initally, the project was started out as a 10-year plan with the total estimated cost of one billion yen, and 370,198 of black pine trees were planted over the area of 103.05 hectares. In March 2021, the first 10year project ended, and immediately moved to the second 10-year plan mainly for maintenance work such as weeding, making drainge canals, and thinning. All in all, the project has been on steady track.

Currently, the on-site work consists mainly of weeding and thinning. So far, about 37,000 trees have benn thinned over the area of 47.44 hectares. Mostly, thinning work has been carried out by local professional forestry workers while local residents and volunteers, many of whom are repeaters, from various parts of the country performaing supporing job. The cut wood is re-used as chips and biomass.

Meanwhile, the United Nations has proclaimed May 22 as the International Biodiversity Day. The coastal forest restoration project has been promoted on the standpoint of conserving biodiversity, and established “biodiversity-friendly zones” in the project site. On the basis of the emvironment impact studies conducted by researchers and volunteers up to 2019, 1,272 plants and animals, and 69 wild birds were confirmed in the area.

Moreover, according to the recent preliminary suveys made by the Natori field manager of the project, the annual carbon dioxide absorption rate is estimated to record 606 tons on the coastal forest.

There are a number of factors that contributed to the successful operations of the coastal forest restoration project, and among other things, the following are said to be cited as the main ones:

1. The project has been implemented under major public-private sector cooperation agrements; The national governmnet, Miyagi prefectural government and Natori municipal government are are all involved in the promotion of the project.
2. It has been carried out with efficient integrated operatin from raising seedlings by local disaster-affected farmers, planting trees by professional forest workers, local residetns and volunteers, and nurturing of forest.
3. OISCA has been utilizing private sector vitality and private funding (project funded solely by donations and grants from private companies and organizations, and private indidivuals in Japan and overseas).
4. Up to the end of March, 2024, the project has created the total number of jobs for 10,412 persons in the local area, and a total of 14,024 volunteers have taken part in the project.

OISCA is thankful to all supporters, for their generous contributions, and we look forward to continued cooperation.