Experimental Planting and Monitoring to Develop Restoration Strategy for the Endangered Epiphytic Orchid, Phalaenopsis japonica

This study reported an experimental re-introduction of the endangered epiphytic orchid species, <i>Phalaenopsis japonica</i>. The three experimental sites were established in Hongdo Natural Reserve in Jeollanam-do, South Korea, each of which differed in vegetation type, aspect, and microclimatic conditions. In 2021, 50 <i>Phalaenopsis japonica</i> individuals were planted to each site (a total of 150 individuals), and survival rate, pest damage, microclimate (air temperature, relative humidity, light intensity, and wind speed) were monitored during 2021-2025. After 6 months, 1 year, and 4 years, we found that 109, four, and one <i>Phalaenopsis japonica</i> individuals survived in the study sites. Redundancy analysis showed that pest damage was the most influential factor causing the initial mass mortality of the planted <i>Phalaenopsis japonica</i> (F=18.4, <i>p</i><0.01). Low light intensity (F=6.1, <i>p</i><0.05), high wind speed (F=5.5, <i>p</i><0.05), and small initial size of <i>Phalaenopsis japonica</i> (F=5.0, <i>p</i><0.05) also contributed to the initial mortality. Overall results suggest that extended cultivation period and pest control after planting might improve initial survival rate of <i>Phalaenopsis japonica</i>. We hope that our results will provide preliminary information to select restoration sites and initial management strategies for the endangered epiphytic orchid species.