• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.334-343
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• 2015

This study was carried out to evaluate quantitatively some properties (density, equilibrium moisture content, shrinkage, water vapor adsorption, water absorptivity, compressive strength, bending strength, hardness and decay resistance) of Larix kaempferi lumber which was heat-treated by hot air and has been used commercially in Korea. Equilibrium moisture content of the heat-treated wood was decreased with increase of hydrophobicity. Dimensional stability of the wood was improved with decrease of shrinkage, water vapor adsorption and free water absorptivity. Also, with the thermo-chemical changes of wood component and lower equilibrium moisture content, decay resistance and compressive strength of heat-treated wood were increased. But, bending strength and hardness of wood were decreased.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.46-57
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• 2001

This study was conducted to provide tending operation information for the effective management in unmanaged artificial forests of Pinus densiflora for. erecta, Pinus rigida, and larix leptolepis, based on the study of the comparison of tree growth pattern by residual stand density after thinning practices. Followings are summarized results of this study. 1. The diameter growth of residual trees was increased as residual stand density decreased by thinning practices in the stands of Pinus densiflora for. erecta, and Pinus rigida, and subcompartment (Ga) and (Na) of Larix leptolepis. The statistical analysis noted that the tree growth was significantly different by the residual stand density. 2. The height growth did not show corresponding results by stand density treatment pattern, which indicated that the height growth was not directly influenced by residual stand density, but by site quality of the stand. 3. The diameter increment for the last six years was proportionately increased in larger diameter classes and less dense stands.

• Journal of Korean Society of Forest Science
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• v.84 no.2
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• pp.186-197
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• 1995

Site-specific allometric equations relating aboveground tree component biomass and leaf area to tree diameter, basal area, sapwood cross-sectional area and sapwood volume were developed using the destructive harvesting method for Pinus rigida Mill., Larix leptolepis Gordon, and Quercus serrata Thunb. stands in Yangpyeong, Kyonggi Province. There were significantly strong correlations between aboveground tree component biomass or leaf area and diameter at breast height (DBH), basal area, sapwood area and sapwood volume. For a similar diameter tree, the three species had a similar stem wood biomass. However, carbon allocation patterns to stem bark, foliage, branch and total aboveground biomass differed among the three species. Specific leaf area and the ratio of leaf area to sapwood cross-sectional area of the three species were significantly different. Allometric equations seemed To be related to leaf habit or leaf longevity. To elucidate the effect of leaf habit or leaf longevity on allometry and canopy characteristics clearly, more intensive studies are needed.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.107-112
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• 2014

The productivity and cost of clear cutting operations were examined to broaden our knowledge on the harvesting system in a Larix leptolepis stand of Korea. The harvesting system was divided into tree operations which were chainsaw (STIHL MS440) felling, tower yarder (Koller301-4) yarding and harvester (WOODY H50) processing. The average cycle time of felling, yarding and processing were 98 s/cycle, 245 s/cycle and 150 s/cycle. The total stump-to-pile operational productivity was 43.07 $m^3/hr$. The highest production activity was the felling 17.93 $m^3/hr$, followed by the productivity of processing 15.62 $m^3/hr$ and then by the productivity of yarding 9.52 $m^3/hr$. In addition the total stump-to-pile operational cost was 24,086 $won/m^3$. The highest cost activity was the yarding 14,557 $won/m^3$ (60.4% of the total cost), followed by the costs of processing 8,461 $won/m^3$ (35.2%) and then by the costs of felling 1,068 $won/m^3$.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.117-126
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• 1997

In fast grown softwood, there are very large changes in material properties going outward from the pith to bark such as anatomical, physical and mechanical characteristics. Some of variations in anatomical properties with annual ring were then examined from Pinus koraiensis, Larix leptolepis, and Chamaecyparis obtusa, which are major softwoods of plantation in Korea. The large variations of annual ring width during young age of tree tended to stabilize after 25year through the transitional period in 17~23year. The ring density was 1.5~2.4 in 1~10year period, and 3.5~6.3 in 30~35year period, in which juvenile and mature wood were certainly assumed to be formed, respectively. Variations of tracheid length showed functional relationships with annual rings as logarithm. Demarcation between juvenile wood and mature wood could be 16~19year, which was determined from increase rate of tracheid length of 0.2%. Cell wall thickness increased with increase of annual ring even though large variations were observed as well. Variations of cell wall thickness within species were pronounced in latewood than earlywood. The increase of cell wall thickness from juvenile wood to mature wood was predominant in Larix leptolepis as 2.0times, and least in Chamaecyparis obtusa as 1.1 times. Cell diameters showed trends of increase during young age of 1~15year, and consistent afterward. The variations of cell diameter between radial and tangential direction were greater in latewood, and most pronounced in Chamaecyparis obtusa.

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.512-520
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• 1994

To enhance the utilization of Larch(Larix leptolepis Gorden) wood, the sawdusts were tested as cultivating media for Lentinus edodes(Mori 290) by varying the composition of the media. The economic efficiency for producing mushrooms from larch sawdusts was evaluated. The results are as follows. 1. Larch sawdust was as much efficient as oak sawdust in the growth of the mycelia and production of good quality of oak mushrooms. 2. The mushrooms were able to be harvested starting six months after beginning the cultivation. No differences were found among the qualities of the mushrooms produced by various treatments. 3. The contents of lignin(28.6-28.7%) in the fresh sawdust of larchwood are higher than those in the residues of the used media(18.2%). But lignin content of 1% NaOH extracts(30.4-34.4%) in fresh sawdust of larch was lower than those in the residues(68.0%). 4. The production of mushroom was relatively high to be 29.7-31.5%(760-780g.)/2.5kg pack) of mushroom weight. The net profit estimated was 1,475Won per pack.

• Journal of Korean Society of Forest Science
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• v.94 no.5 s.162
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• pp.302-306
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• 2005

Litterfall and nutrient inputs were measured in even-aged coniferous plantations (a 31-year-old Pinus rigida and a 31-year-old Larix leptolepis) on a similar site condition in the Forest Practice Research Center, Gyeonggi Province. Litterfall was collected monthly from circular littertraps (collecting area: $0.50m^2$) for three years between April 1997 and February 2000. Average total annual litterfall was significantly higher for pine (5,802 kg/ha/yr) than for larch (4,562 kg/ha/yr) plantations. Needle litter in both plantations accounted for about 63% of total litterfall. Litterfall in the larch was distributed as follows: needle > other leaf > branch > miscellaneous > bark, while it was needle > miscellaneous > other leaf > branch > bark in the pine plantation. There was no temporal variation in needle litter, other leaf and bark during the 3 year study period. The concentrations of all nutrients (N, P, K, Ca, Mg) in needle litter were significantly higher in the larch than in the pine plantations. The annual nutrient concentration of needle litter in the larch varied among the years, whereas no year variation of needle litter was in the pine except for phosphorus (P). Nitrogen (N) and P inputs by needle litter were significantly higher for larch than for pine plantations established on a similar soil. The differences in N and P inputs were attributed to lower nutrient concentration in pine needle litter compared with larch needle litter, not to total needle litter mass. Annual inputs of nutrient in both plantations were not significantly different among years except for K of the larch although there was yearly different in needlefall mass and nutrient concentration during the 3-year observed period. The results indicate that the mechanisms of litterfall and nutrient inputs vary considerably between pine and larch plantations established on a similar site condition.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.229-233
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• 1999

The possibility for long-term preservation of Larix leptolepis embryogenic tissue was tested in this study. Higher relative increase of the tissue fresh weight was observed when embryogenic tissue was pretreated for 24 hrs in a medium containing 0.4 M sorbitol or 20% polyethyleneglycol with cooling rate of -0.33$^{\circ}C$/min. The fast cooling rate of -0.5$^{\circ}C$ and -1.$0^{\circ}C$/min appeared to be less effective in regrowth of tissues from cryopreservation. No DNA variants have been observed by PCR analysis among the embryogenic tissues recovered after 1-, 7-, and 28-day-cryopreservation. The post-thaw embryogenic tissue gave rise to mature somatic embryos which developed into plants.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.78-84
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• 2000

Two flavanones and one flavone were isolated from the diethylether soluble fraction of ethanol extract of Larix leptolepis heartwood. These compounds were identified 3,3',4',5,7-pentahydroxyflavanone(taxifolin), 3,4',5,7-tetrahydroxyflavanone(aromadendrin) and 3,3',4',5,7-pentahydroxyflavone(quercetin) by instrumental analyses using UV, IR, MS and NMR spectrometries. Antioxidative activies of these compounds were investigated by 1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical scavenging activity. Quercetin and taxifolin indicated high free radical scavenging activities compared to ${\alpha}$-tocopherol and BHT(butylated hydroxytoluene).

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.522-530
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• 2019

Two edible plants, Allium victorialis var. platyphyllum and Ligularia stenocephala, and one medicinal plant, Panax ginseng, were cultivated in the understory of an artificial Larix kaempferi plantation for ten years. Growth characteristics (number of leaves and flower stalks per plant, and leaf length and width), survival rate, and yield (fresh weight of plants) per unit area (1 ㎡) were investigated one year after planting, and six and ten years following cultivation. P. ginseng and L. stenocephala survived at a high percentage for two years after planting. Results showed that P. ginseng had longer and thicker roots when aged; however, a large number of plants died and the yield was low. In contrast, almost half of A. victorialis var. platyphyllum died within two years of planting. The surviving plants grew well for ten years and the yield was increased. The leaf length and width of L. stenocephala increased; however, the survival rate and the number of leaves per plant decreased as the period of cultivation was extended. In contrast, A. victorialis var. platyphyllum survived at a lower rate (50%) than the two other crops (98% for L. stenocephala and 83% for P. ginseng) during the early cultivation period, with little change in the survival rate over an extended time; however, the yields increased. This species showed an increase in the number of flower stalks and leaves, and as a result, the larger leaves increased the yield. We evaluated the understory cultivation of three crops in a L. kaempferi plantation under natural conditions, with no irrigation or fertilization, and Allium victorialis var. platyphyllum showed the greatest growth potential among the three tested crops.