In Korea, pine trees are both culturally and spiritually important. According to the fourth forest resource survey from 1996 to 2005, pines occur widely on some 1,507,118 ha of land representing 23.5% of Korea’s forest area and 15.1% of the country’s land mass (Kwon 2006). Pines have been the dominant tree species in Korean forests even after the attack by the pine caterpillar in 1970s, the outbreak of pine needle gall midge in 1980s, and the occurrence of black pine blast scale in 1980s and 1990s. Because of the serious losses from pine wilt disease, which was first reported in Busan in 1988, this disease is a serious threat to Korea’s pine forests (Yi et al. 1989). Despite the strenuous efforts to manage the disease over the last 19 years, pine wilt has spread to Mokpo, Sinan, and Yeongam in Jeonnam Province (west), Daegu, Gumi, and Andong in Gyeongbuk Province (inland), and Gangneung and Donghae in Gangwon (northeast) (Fig. I.10). Since 2006, at least in the southern Korea, spread of the disease has slowed as the result of intensive management (Fig. I.11). Until 2005 Japanese red pine (Pinus densiflora) and Japanese black pine (P. thunbergii) were reported as natural hosts of pine wilt disease in Korea; however, in 2006 Korean white pine (P. koraiensis) was found as being affected by pine wilt disease. This section gives a brief history and management strategy for pine wilt disease in Korea.