Jeju uprising to Jeju from Busan and deploying police companies, each 1,700 strong, from the southern provinces of the mainland. The guerrillas retreated to their bases in the forests and caves around Hallasan, an extinct volcano and the highest mountain in South Korea. On April 29, the Korean, non-military, governor of Jeju province abandoned his post, defected, and joined the guerrillas. This caused many police officers, disillusioned by the atrocities they were ordered to commit against their own, to do the same. In response, U.S. military provincial governor William F. Dean ordered a purge of SKLP sympathizers from the ranks of the
Hallasan caused by ticks is still continuing these days. Six tick species give damage to domestic animals. According to the world floral region, Hallasan belongs to the temperate subregion with Yangtze River basin and southwest Japan. From the coast to the top of the Hallasan, plants are distributed vertically from the subtropical plants to the alpine plants due to the environmental gradient. Of the 4,000 species of vascular plants native to Korea, about 400 species are estimated to be endangered or potentially rare. Especially, 23 species-specific wild plants designated by the Ministry of Environment ( totally 59 species ) are distributed