Crown Fuel Characteristics and Allometric Equations of Pinus densiflora in Gyeongbuk Province, Korea

The crown fuel characteristics of the most dominant coniferous species in Korea, Pinus densiflora, were investigated in Gyeongbuk province, Korea. Allometric equations using DBH as independent variable were also developed for the estimation of crown fuel load (needles, branches: <0.5 cm, 0.5-1 cm, 1-2 cm, and 2-4 cm in diameter), crown volume, and aboveground biomass. The average crown bulk density in Youngju and Bonghwa was 0.47 kg m-3, while in Daegu, it was 0.29 kg m-3. The crown bulk density of needles and branches with a diameter of <1 cm was 0.21 kg m-3in Youngju, 0.27 kg m-3 in Bonghwa, and 0.13 kg m-3 in Daegu. The average crown base height was 5.10 m in Youngju, 5.20 m in Daegu, and 3.60 m in Bonghwa. Overall, the Pinus densiflora stand in Bonghwa is more hazardous if crown fire occurs compared to the other study sites based on different crown fuel characteristics. The allometric models developed were able to explain at least 79% of the observed variation in the biomass and crown volume. For the aboveground biomass, Daegu had the highest mean tree biomass with 103.54 kg, followed by Youngju (67.35 kg) and then Bonghwa (37.72 kg).