In order to investigate biomass yield of one-year-old hyblrid poplars, Pripulusalba x P. glandulosa $F_1$ and Populus nigra var. italica x P. maximowiczii $F_1$clones, as energy and fiber resources, dry matter yield, leaf area, leaf area index, dry matter production ability, specific gravity and fiber length and width were measured. Dry matter yield was 1.89 ton/ha for Poplus alba x P. glandulosa $F_1$ and 3.63 ton/ha for Populus nigra via.italica x P. merximowiczii $F_1$ clones in the planting density of 20,000 trees/ha and in the planting density of 40,000 trees/ha was 3.87 ton/ha for Populus alba x P. glandulosa $F_1$and 5.64 ton/ha for Populus nigra var. italica x P. maximowiczii $F_1$ clones. Leaf area index was 1.24mtim2 in the planting density of 20,000 trees/ha and 2.45 m31m3 in the density of 40,000 trees/ha for Populus alba x P. glandulosa $F_1$ clones and it was 1.96 m21m2 in the planting density of 20,000 trees/ha and 3.36 m21m2 in the density of 40,000 trees/ha for the hybrid $F_1$ Populus nigra var. italica x P. maximowiczii clones. The average specific gravity of the hybrid poplars was 0..36 when bark and pith were included and 0.31 when bark and pith were removed in the plot of 20,000 trees/ha and in the 40,000 trees/ha plot showed 0.35 and 0.31 respectively, for Populus alba x P. glandulosa $F_1$clones. It was 0.36 when bark and pith were included and 0.32 when bark and pith were removed in the 20,000 trees/ha plot and in the 40,000 trees/ha plot was 0.34 and 0.31 respectively for Populus nigra var. italica x P. maximowiczii $F_1$clones. The average fiber length was 0.57 mm in the 20,000 trees/ha plot and 0.58 mm in the 40,000 trees/ha plot for Poplus alba x P. glandulosa $F_1$clones and was 0.60 in both plots of 20,000 trees/ha and 40,000 trees/ha for Populus nigra var. italica x P. maximowiczii $F_1$ clones. There is a big clonal variation among those clones studied, showing high selection potential in both species.

P. alba x glandulosa의 생장은 산록부에서는 양호하나 산정부로 올라갈수록 생장이 떨어지는 원인을 구명코자 생장과 토양 인자간의 상관관계를 조사하였다. 1. 각조림지는 연평균생장량으로 산정부는 수고 0.7m 인데 비하여 산록부는 1.29m 로서 184$\%$나 생장이 빠르고 직경생장에도 218$\%$나 빠르다. 또한 산록부에서 산정까지의 사거리가 길수록 산복까지 생장이 비슷하여 생장의 감소율이 완만하고 사거리가 짧을수록 생장의 감소율이 급격하여 산록부에만 생장이 좋고 그위는 불량하다. 2. 토양함수율과 수고 및 직경과의 상관계수는 각각 r=0.76, r=0.71로서 높은 상관관계를 나타내고 또한 토심과 수고(r=0.65) 및 직경(r=0.79)과도 높은 상관관계를 나타내며 경사도와 생장은 부의 상관을 나타내고 있다. 이와같이 이들 세인자가 생장에 가장 영향을 많이 주는 것으로 생각되며 대체로 산록부는 토심이 깊고 경사가 완만하여 토양수분이 높았다. 3. 유기질과 전질소도 수고 및 직경생장과 각각 상관관계가 있으며 5$\%$의 유의성이 있었고 산록부에 유기질과 전질소의 함량이 높았다. 4. 가리와 수고생장고, 칼슘 및 토양산도는 직격생장과 각각 상관관계가 있으며 이들 요인들은 생장에 어느정도 영향을 주는 것으로 사료되며 5. 그러나 유효인산, 마그네슘, 망강은 생장과 상관관계가 없었다.

To survey the present qualities of the molded and to present the base line of qualities in manufacture, the charcoal collected at 27 makers through the nation were examined. The molded charcoal examined in this paper, which is made by carbonization and molding of sawdusts from wood industries, is widely used to kindle holed-coal-briquette. The holed-coal-briquette is utilized in cooking and heating as primary energy source of ordinary households in this country. The average qualities of molded charcoal was as follows; ash content 13.95$\%$, weight 184.6g, density 0.47, time of kindling holed-coal-briquette 65.4 min., calorie 5,790 kcal/kg. The ten makers produced inferior qualities, that was 37 per cent of the 27 makers examined. The base line of qualities of molded charcoal was defined as follows; ash content below 17$\%$, weight above 175 g, falling strength above 300 mm, calorie above 5,500 kcal/kg.