• Journal of Korean Society of Forest Science
• /
• v.69 no.1
• /
• pp.28-35
• /
• 1985

To estimate the aboveground biomass of Pinus rigida and Pinus rigida ${\times}$ taeda 22-year-old plantations, the experimental plots of $200m^2$ in size located in Kwangju of Jeonlanam-do were selected. Nine sample trees selected at each plot taking account of DBH distribution were felled and the diagram of oven-dry weight distribution of stem, branch, and needle for each 1m segment was constructed. The logarithmic regression equations between dry weight of each component (stems, branches, and needles) and the variable of $(DBH)^2{\cdot}H$ were obtained. The aboveground standing crops was estimated to be as much as 71.61 and 142.32 tons of dry matter per hectare in P. rigida and P. rigida ${\times}$ taeda stand respectively. The net production was estimated as 10.81 and 10.46 t/ha/yr and the net assimilation rate 1.32 and 1.00 kg/kg/yr in P. rigida and P. rigida ${\times}$ taeda stand respectively. And the efficiency of needles to produce stem was 0.97 and 0.81 kg/kg/yr in same order.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.8 no.1
• /
• pp.10-14
• /
• 2006

We tested the seed viability of Pinus rigida using accelerated aging to discover optimum times and temperatures far artificially accelerated aging. Seeds were artificially aged at different temperatures and during different tines. The seed viability was affected by the accelerated aging and by temperature with a decline in germination and seed vigor. The aging index of P. rigida seed was 0.31 at $35^{\circ}C$ and seed viability was nearly lost after aging treatment at $40^{\circ}C$ for 15 days. The optimum temperature of P. rigida far the aging test was decided to be approximately $37^{\circ}C$ on the basis of the aging index. Inorganic materials and conductivity of leaching solution from aging seeds increased with the increase of aging period. The accelerated aging test was considered to be a suitable method to evaluate the seed viability of tree species. Because seed characters are much different among tree species, however, more studies need to be done to discover the optimum conditions for aging by tree species.

• Journal of the Korean Wood Science and Technology
• /
• v.32 no.2
• /
• pp.90-95
• /
• 2004

Pitch pine (Pinus rigida) has been planted in Korean forests for several decades, primarily for erosion control and use as a fuel supply. To enhance its value, and especially potential use as lamina for structural glued laminated timber (glulam), log quality and lumber yield of pitch pine were evaluated in this study. Trees from pure pitch pine stands with an average diameter at breast height of 32 cm were felled and bucked into 3.6m long 15 cm minimum butt-end diameter logs. Over 80% of the logs were classified to No.2 or No.3 visual grade group. Upon sawing total lumber yield was 55.2%, 39.9% for structural glulam lamina, 7.2% for louver, and 8.1% for miscellaneous use. The final lumber yield for manufacturing structural glulam, after cross-cutting to eliminate knots and finger jointing, was only 15.3%. To enhance this manufacturing yield requires that the rate of knot-included lumber used as lamina be raised. However arrangement of the knot-included lamina, whose mechanical properties need to be accurately evaluated, must be optimized to minimize any reduction to the structural glulam strength. The log quality and lumber yield of pitch pine evaluated in this study are expected to facilitate proper planning for wood product manufacture in the Korean lumbering and glulam industrial field, which has not previously dealt with this species.

• Journal of Korean Society of Forest Science
• /
• v.102 no.4
• /
• pp.578-586
• /
• 2013

This study was performed in Pinus rigida and Larix kaempferi plantations which occupy approximately 60% of artificial forest area in Korea. The objective of this study was to know the differences in soil physical and chemical properties between both plantations. Soil physical and chemical properties from published literature and analyzed soil data in national forest in 2010 and 2011 were analyzed by plantation regions and stand age of 5 years unit. Jeollanamdo in Pinus rigida plantations and Gyeongsangbuk-do in Larix kaempferi plantations showed higher soil chemical properties than those of other regions. Soil texture in both plantations was almost loam and sandy loam. Mean soil pH in Pinus rigida and Larix kaempferi plantations were 4.86 and 4.87, respectively and there was no relationship between soil pH and stand age. The mean concentrations of total nitrogen (%) and available phosphorus (mg $kg^{-1}$) were 0.21 and 11.00 for Pinus rigida plantation and 0.28 and 13.32 for Larix kaempferi plantation. In Larix kaempferi plantation, total nitrogen, available phosphorus and organic matter concentrations and C.E.C. were higher than those in Pinus rigida plantation and showed positive relationship with stand age. This positive relationship was also revealed between the exchangeable cations and soil pH. The results of this study provide an informative data in selecting tree species for planting and contribute to the establishing forest management plan for the maintenance of sustainable forests resources.

• Journal of the Korean Wood Science and Technology
• /
• v.17 no.3
• /
• pp.8-19
• /
• 1989

The proportion of imported wood has been now over 80% of raw materials needed in the wood industry, and therefore, many of studies on the substitution of domestic wood for imported wood and on the increasing the utilization rate of domestic species have been attempted and considered as very important projects to solve. But these trials were practically restricted by several disadvantages of domestic species. such as a small diameter, variety of species, and irregularity of wood physical or chemical characteristics, etc. From a this point of view, this study was carried out to investigate solid wood bending properties of sample trees and then to develop their end uses. The species of sample trees were Pinus densiflora S. et Z., Pinus rigida Mill., and Larix leptolepis Gord. which have large growing stocks but Pinus rigida and Larix leptolepis have not been used well because of their poor qualities. The results obtained were as follows: 1. The optimum conditions for solid wood bending processing of Pinus densiflora, Pinus rigida, and Larix leptolepis are showed in Table 6. 2. The minimum solid-bending radii of Pinus densifjora, Pinus rigida, and Larix ieptolepls were 260mm, 240mm, and 300mm, respectively in steaming treatment.

• Journal of the Korean Wood Science and Technology
• /
• v.43 no.3
• /
• pp.374-380
• /
• 2015

The quality characteristics of the woodpellet manufactured from two domestic pines (Pinus densiflora S. et Z. and Pinus rigida Mill.) were investigated for the efficient energy use of woody biomass resources. Properties of woodpellets such as moisture content, heating value, ash content, apparent density and durability were determined by using the standard test method of woodpellets of Korea Forest Research Institute (KFRI) and elemental analysis. The results of elemental analysis for C, H, O and N showed 61.42% carbon, 5.56% hydrogen, 32.87% oxygen, and 0.15% nitrogen for Pinus densiflora S. et Z. and 61.03% carbon, 5.96% hydrogen, 32.83% oxygen, and 0.18% nitrogen for Pinus rigida Mill. No significant difference between Pinus densiflora S. et Z. and Pinus rigida Mill was observed on elemental analysis. Heating values of each woodpellet were ranged from 19.00 to 19.42 MJ/kg which satisfied the first grade quality standard (${\geq}18.0MJ/kg$) by KFRI. The ash contents of woodpellet were slightly different between Pinus densiflora S. et Z. and Pinus rigida Mill., and satisfied the first grade quality standard (${\leq}0.7%$) by KFRI. Apparent density of woodpellet (Pinus densiflora S. et Z.) was passed the first grade standard level (${\geq}640kg/m^3$), and woodpellets from Pinus rigida Mill. satisfied the second grade quality of the standard. The moisture contents of each woodpellet were satisfied by the first grade quality standard (${\leq}10%$). The durability of woodpellet (Pinus densiflora S. et Z.) was passed the third grade level (${\geq}95%$), but Pinus rigida Mill. woodpellet was insufficient to satisfy the quality standard.

• Journal of Korean Society of Forest Science
• /
• v.65 no.1
• /
• pp.1-11
• /
• 1984

Susceptible trees of Pinus densiflora and resistant trees of Pinus rigida following pine gall midge (Tnecodiplosis japonensis Uchida et Inouye) attack were seasonally compared to examine the variation in needle growth and photosynthetic ability, respiration rate, chlorophyll contents, carotenoid and anthocyanin contents. Also, carotenoid and anthocyanin contents of larvae both from soil and from galled tissue were compared during March and September, respectively. The plantation damaged severely by this insect consisted mostly of 10-to 15-year old P. rigida and P. densiflora. The results obtained in this study were as follows: 1) The length of the infested needles of P. densiflora decreased by 48.1 percent compared with the normal needles, while that of P. rigida did 37.4 percent. 2) All of P. densiflora and P. rigida showed higher photosynthetic ability in normal needles than in infested needles. The maximum photosynthetic ability of P. densiflora was shown in mid-August, while that of P. rigida in mid-October. In contrast to that, respiration rate of infested needles was higher than that of normal needles in both species. The respiration rate of P. rigida was higher than that of P. densiflora. 3) P. rigida had higher total chlorophyll contents than P. densiflora. The total carotenoid contents tents in infested needles were higher than those in normal needles of both species. 4) Total carotenoid contents were generally higher in P. rigida than in P. densiflora during the growing season. The total carotenoid content (0.094mg/g) in larvae from soil was similar to that (0.092mg/g) in larvae from galled tissues. 5) Infested needles of both species showed higher anthocyanin contents than normal needles. Higher anthocyanin contents in galled needles were due primarily to its active formation stimulated by larval attack. Thus, reddish-brown coloration occurred only in galled needles of P. densiflora.

• 한국생태학회:학술대회논문집
• /
• 1999.05a
• /
• pp.112.2-112.2
• /
• 1999

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 1994.04a
• /
• pp.123-130
• /
• 1994

• The Science & Technology
• /
• no.1 s.452
• /
• pp.106-107
• /
• 2007