A commercial plantation in the shape of a circle

Two curious “crop circles” are seen in Miyazaki Prefecture in Japan. They are only visible from the air and formed by sugi trees (Japanese cedar).

According to documentation (PDF) from the Japanese Ministry of Agriculture, Forestry and Fisheries, an area near Nichinan was designated “experimental forestry” in 1973. One of the experiments was to try to measure the effect of tree spacing. Growing trees. The experiment was carried out by planting trees in 10-degree radial increments forming ten concentric circles of varying diameters. They planted cedar circles near Nichinan in Miyazaki Prefecture, with smaller inner circles gradually expanding into larger radii to create the perfect ten rings.

Part of what makes crop circles so attractive is their concave shape, an unexpected result of the experiment suggesting that tree density affects growth. The trees will be harvested in about five years, but officials are considering preserving crop circles.

You may be interested in reading: The correct recipe for pine planting density.

Miyazaki Prefecture is famous for Japanese cedar. In the Naka area, it is called valve armor as a shipbuilding material.

A “forest density test forest” began to be planted to respond to the demand for wood. In the test forest, it was changed from sparse planting to dense planting, with differences in planting density to demonstrate the growth and material change process.

36 cedars were planted at the intersections with 10° radiation, and the density per hectare increased to 377. It is established at 10,027 individuals.

Therefore, when viewing this forest from the sky, the trunk is concentrically spreading and turning into a subject that looks like a “crop circle”.