United States Civil Administration of the Ryukyu Islands
Okinawa's demand for wood outstripped the ability of the forests to renew themselves on their own, naturally, and the combination of deforestation and rainy weather including regular typhoon seasons led to extensive erosion and landslides. Sai On is particularly known for the forestry and soil conservation efforts undertaken under his guidance to combat these problems. Particular trees and sections of forest throughout the islands are still today called　"Sai On pines" (蔡温松, "Sai On matsu"; 蔡温並木, "Sai On namiki"), and his essays on the subject of forestry and conservation remained so valued that the post-war United States Civil Administration of the Ryukyu Islands translated, published, and distributed them abroad in 1952. In addition to these essays, Sai On produced a number of other documents, including a handbook for administrative officials in the provinces entitled "Yomui-kan", and "Ryokōnin Kokoroe" (旅行人心得), or "Travelers' Advice", a guide for Okinawans abroad in China to help them in obscuring from the Chinese the relationship between Okinawa and Japan's Satsuma Domain.