• Journal of the Korean Wood Science and Technology
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• v.41 no.3
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• pp.221-233
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• 2013

This study was performed to identify the effect of end-coating around pith of heavy timbers of Red pine and Korean pine on high temperature and low humidity drying characteristics. Total drying times were 268 hours, and ranges of final moisture content was investigated that Red Pine 9.2% to 10.8% MC for square and round timber, in case of Korean Pine 15.0% to 22.0% MC for square timber, 12.8% to 20.4% MC for round timber. Moisture content distribution of Red Pine was a uniform, but part of high moisture content was found in Korean Pine. In case of Korean pine, the surface checks were occurred more severe than in case of Red pine, and end-coating treatment were investigated to be ineffective on surface check. The internal checks were only formed on the two timbers. The value of the case hardenings was investigated that the ranges 3.7% to 9.1% for Red pine. In case of Korean pine, on the other hand, the case hardenings presence a few as 20.9% to 35.8%.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.128-133
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• 2002

This study was conducted to investigate the influence of storage time on the sapstain development of Japanese red pine and Korean pine logs during storage in log yard, and their stain characteristics. Japanese red pine and Korean pine trees were harvested and cut into logs in mid January of 2001. These logs were transported to the two local sawmills where they were closely stacked in remote parts of log yard. The logs were then sampled destructively by cutting seven to nine 3-cm long discs along the length of each log at intervals of 3, 4, 5, 6, and 8 month after felling. The stain coverage and maximal radial penetration of stain were measured from the discs of the sampled logs after the isolation of causal staining fungi. The sapstain was primarily infested by the attack of bark beetles and the species of bark beetle was identified as Tomicus piniperda. The main fungal species isolated from stained wood was Ophiostoma species. Based on the present study, the logs could be stored in log yard until May without stain; but stain development was rapid after May and the severity of stain increased proportionally with storage time. Korean pine was more susceptible to fungal stain than Japanese red pine. During summer storage, decay started to develop in logs and the main species were identified as Tyromyces sp. and Schizophyllum commune. Information provided in this paper would be very useful to develop more effective control strategies for sapstain prevention in Japanese red pine and Korean pine logs.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.437-448
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• 2018

Physical characteristics of Korean red pine (Pinus densiflora) were investigated with different cultivation locations in Taebaek Mountains as Goseong-gun, Hongcheon-gun and Bonghwa-gun as experimental sites. Moisture content based on air-dried or green (artificial) wood was no significant differences with different cultivation places. Specific gravities of both sapwood and heartwood of red pine from Bonghwa-gun were higher than those from other two sites (Hongcheon-gun or Goseong-gun). Specific gravity of heartwood of red pine from Goseong-gun was higher than it from Hongcheon-gun, but this trend was opposite in case of sapwood. Higher specific gravity of red pine heartwood from Goseong-gun maybe resulted in higher strength than those of other sites. In shrinkage ratio, there was no significant difference among different cultivation places in radial directions, but red pine from Bonghwa-gun was higher than those of other sites in tangential directions. Hygroscopicity was no significant differences with different cultivation places. These results will be helpful information for efficient use of pinewood and good quality of pinewood production for genetical breeding improved.

• Journal of the Korean Wood Science and Technology
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• v.47 no.6
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• pp.732-750
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• 2019

Air drying was carried out on 15 Korean red pine logs to provide a prediction model of the moisture content (MC) change in the wood during drying. The final MC was 17.4% after 880 days since the beginning of air drying in the summer for 6 Korean red pine logs with 68.7% initial MC. The final MC was 16.0% after 760 days since the beginning of air drying in the winter for 9 Korean red pine logs with 35.8% initial MC. A regression model with R-squared of 0.925 was obtained as a result of multiple regression analyses with initial MC, top diameter, temperature, relative humidity, and wind speed as independent variable and and MC change during air drying as dependent variable. The initial MC and top diameter, which is the characteristic of Korean red pine, have greater effect on the MC decrease during air drying compared to meteorological factors such as the temperature, relative humidity, and wind speed. Two-dimensional mass transfer analysis was performed to predict the MC distribution of Korean red pine logs during air drying. Two prediction models with different air drying days and different meteorological factors for the determination of the diffusion coefficient and surface emission coefficient were presented. The error between the different two methods ranged from 0.1 to 0.8% and the difference from the measured value ranged from 2.2 to 3.6%. By measuring the internal MC during air drying of Korean pine logs with various initial MC and diameter, and calculating the moisture transfer coefficient in wood for each meteorological condition, the error of the prediction model can be reduced.

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.56-65
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• 2009

In Korea, Red pine(Pinus densiflora) stands at a very important place, historically, culturally, and emotionally and it is one of the tree species that can produce domestic timber as forest resources economically. The growing space for Red pine forest in Korea is gradually reducing while the space for deciduous tree forests including oak series is gradually increasing. Thus, it is required that the research work should be done on renewal for pine forest retention and its related forest management practices. This research aims at developing stable, sustainable management forests and inducing nature renewal by grasping growth environment and succession process through the pattern of stand and structure analysis of the red pine(Pinus densiflora) for central region. The pine forests in central region were classified into four communities, such as Acer pseudo-sibolianum, Quercus acutissima, Lindera erythrocarpa, and Pinus densiflora and they are showing different characteristics by pattern according to their growing district. There appeared a lot of red pines in the upper layer, but there existed high weight of broad-leaved forest tree species, such as oak series in the middle layer and the appearance of the red pine was meager in the lower layer. Therefore, it appears that the red pine has a high influential ecological strength in terms of correlativity; however, if the red pine in tree layer is dead by aging in nature state with the lapse of time, it is considered that oak species, such as Quercus mongolica, Quercus variabilis, and Quercus serrata will be dominant below sub-tree layer. In addition, there appear differences in characteristics and growth pattern of the red pine forest depending on stand pattern, so it is considered that a differential application method should be employed in the pine forest management.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.305-312
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• 2010

The purpose of this study is to compare the relative growth of annual ring width of red pine(Pinus densiflora), black pine(Pinus thunbergii) and pitch pine(Pinus rigida) by means of multiple regression method according to Graybill hypothesis. The obtained results are as follows. 1. The changes of rainfall have affected to tree growth during the periods of 1975 through 1978. 2. Among these pine trees, red pine was mostly influenced by environmental factors. 3. The growth of annual ring width was sensitively responded to the changes of rainfall and air temperature. 4. Among the heavy metals analyzed, the concentrations(ppm) of Lead(Pb) and Copper(Cu) were negatively effected on the growth of annual ring width of pine trees. 5. The analytical technique of annual ring width may be useful for estimation of the pollution in forest areas near industrial complexes.

• Journal of the Korea Furniture Society
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• v.19 no.3
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• pp.156-162
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• 2008

Three major domestic softwoods, Korean red pine, Korean pine and larch, were heat-treated at $220^{\circ}C$ and for various treatment times for color changing. A new heat treatment equipment was developed for this study and was revealed working well for changing the colors of the three softwoods. The color difference index of 15 was obtained after 8 hours for Korean red pine and Korean pine, and 10 hours for Larch. The correlations of brightness, redness and yellowness with treatment time were different between species.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.255-262
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• 1996

This study was carried out to investigate the effects of soil fertilizers on wax content, contact angle, mineral nutrient content of Japanese red pine (Pinus densiflora Sieb, et Zucc.) leaves and soil acidity of Japanese red pine communities in Namsan and Kwangnung to see whether they can recover forest decline. Japenese red pine communities were treated with $Ca(OH)_2$, $Mg(OH)_2$, $Ca(OH)_2+Mg(OH)_2$+C.F.(compound fertilizer) in a randomized complete block design with 3 replication from November, 1990 through October, 1993. Wax content, contact angle value and mineral nutrient content of Japanese red pine leaves and soil pH of communities were measured and the results obtained are as follows: 1. Contact angle value and wax content of Japenese red pine leaves increased when the fertilizers were applied in soil. The order leaves grew, the smaller their contact angle values. 2. K and Ca contents of Japanese red pine leaves were higher in Namsan than in Kwangnung, whereas Mg content was higher in Kwangnung. K and Mg contents of the leaves increased with fertilization both in Namsan and Kwangnung. 3. Soil acidity of pH 4.2 ~ 4.3 was shown in Namsan and pH 4.6 ~ 4.9 in Kwangnung. No acidity changes were shown when the fertilizers were applied in soil. However with the lapse of the soil fertilizer application time, there was the indication that soil pH became higher in the fertilizer treatments than in the control.

• Journal of the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.13-20
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• 2005

This paper deals with flexural vibration techniques as a means of predicting bending strength properties for quarter-sawn and flat-sawn planes of red pine containing knots. Dynamic modulus of elasticity $(MOE_d)$ was calculated from resonance frequency obtained from the flexural vibration induced by a magnetic driver in quarter-sawn and flat-sawn planes of red pine containing knots. The dynamic MOE were well correlated to bending strength properties. Their correlation coefficients ranged from 0.866 to 0.800 for the regression between dynamic MOE and static bending MOE or MOR. The difference of the values between quarter-sawn and flat-sawn was very small. These values were higher than correlation between percentage of total knot diameter to total width of red pine specimen $(K_T(%))$ as well as $K_O(%)$ base upon ASTM D 3737 and static bending strength properties (correlation coefficient r = 0.448~0.704), and were similar to those between static bending MOE and bending MOR (r = 0.850). These results indicate that dynamic MOE obtained from resonance frequency induced by flexural vibration of magnetic driver is able to effectively use for predicting of static bending strength of red pine containing knots as well as static MOE.

• Mycobiology
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• v.29 no.4
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• pp.205-209
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• 2001

The Korean sawmills have recently recognized the importance of prevention of fungal discoloration due to increased losses in revenue. Before establishing integrated control strategies of fungal discoloration, more complete knowledge about causal organisms is needed. As a first step, we initiated a through survey of fungi colonizing commercially important softwood(Pinus dens flora, Pinus koraiensis, and Pinus radiata) logs and lumber in Korea. In this paper we report results obtained from Japanese red pine(Pinus densiflora) log study. In summer 2000, fungi were isolated from Japanese red pine logs in storage, and identified based on their cultural and morphological characteristics. A total of 595 fungi were isolated, representing 21 genera and 30 species. Mold fungi, mostly Trichoderma species, were the most frequently isolating fungi, representing more than half of all isolates. Dematiaceous fungi represented approximately one fifth of the isolates, and Rhinocladiella atorvirens was the most abundant in all samples. Opiostoma species represented 7% of all isolates from cores planted on malt extract agar(MEA) and the incidence of these species doubled with the addition of streptomycin and cycloheximide to MEA. The results indicate that Japanese red pine sapwood is susceptible to colonization by a variety of fungal species. As a result, control strategies that concentrate on one fungus may have limited success because of interference from competing flora.