"Ryukyu-matsu" (Pinus luchuensis) belongs to Pinaceae (the Pine family). It is a tall evergreen tree that is endemic to Japan and is distributed from the south of the Tokara Islands in Kyushu to the Okinawa Islands. This tree grows near the coast and is about 20 m high. The canopy is flat, umbrella-shaped, the bark is grayish black, with irregular cracks. The leaves are linear and two bundles. It is monoecious and blooms from March to April. The fruit is a cone, ovate with a diameter of about 2 cm. It is designated as a prefectural tree in Okinawa Prefecture. It is also called "Okinawa pine" by another name.