Abstract: Pine wilt disease has known as a serious forest disease in East Asia such as Japan, Korea

and China. Fumigation and burning are considered as best way to treat infected tree at early detection. For

investigate spectral reflectance characteristics of infected trees, periodic measurement has been done in both

infected and non-infected trees. Infected and non-infected trees’ reflectance (400 nm~2,500 nm wavelength) are

detected from June to October with GER3700 spectrometer. Noise of reflectance data was corrected using cubic

spline interpolation method. Reflectance was changed in most of infected trees with ranges Red (600 nm~700

nm) and Middle Infrared (1,400 nm~1,500 nm) within two months after injected by Pine Wood nematode

(PWN), but there was no differences in non-infected trees. Infected and non-infected trees were compared

statistically in each period. As a result, we found that a statistically significant difference was occurred at Red

and Middle Infrared (MIR) 2 months after injection (p<0.05), however, no significant difference in near infrared

(p>0.05). Therefore, the early detection of infested pine trees by PWN may possible through detecting the

change of spectral reflectance at red and MIR.