• Korean journal of applied entomology
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• v.32 no.2
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• pp.168-175
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• 1993

This study investigated the composition and distribution of the soil microarthropods community in plantations of the Korean pine(Pinus Koraiensis SIEB. et ZUCC, the sudong area, Namyangju-gun, Korea) , which had been planted in different years. The soil samples intended to collect soil animals were taken monthly from June 1988 to July 1989. The composition of soil microarthropods community included Arachnida, Chilopoda, Insecta, Collembola, Diplopoda, Crustacea, and Symphyla. The Acarina were composed of 82.4% of Cryptostigmata, 8.0% of Mesostigmata, 7.9% of nymphs, and 1.7% of others. The Insecta included six orders including Hymenoptera(65.8%) and Diptera(13.9%). Population densities increased from when the plantations were first established until the planting were 25 years old, after which they declined. Population densities of the soil microarthropods were highest in July and lowest in January. The Collembola/Acarina ratio is 0.16 overall, and was highest in January and lowest in August.

• Journal of the Korean Wood Science and Technology
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• v.24 no.1
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• pp.11-16
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• 1996

The purpose of this paper is to present a summary of assignment design values according to domestic softwood structural lumber grading rules. Allowable stresses for visually graded lumber were determined from basic data on small. clear specimens. The data corrected for variability such as natural defects and other factors. The procedure adopted by Japan was used for assigning allowable design values. Strength ratios in relation to each defect were taken from ASTM D 245-81. Korean pine(Pinus koraiensis S. et Z.), Korean red pine(Pinus densiflora S. et Z.), Japanese larch(Larix leptolepis Gordon) and Needle fir(Abies holophylla Max) were applied to this study. The calculated allowable stresses were same in Korean pine and Korean red pine. These values were highest in Japanese larch lowest in Needle fir. So, it is desirable for these species to be classified into different catagories Species Group. However, accurate comparison in design values on lumber grading rules among U.S., Japan and Korea was somewhat difficult. And full scale testing will be necessary for accurate determination of the correction factors to setting up design values.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.110-118
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• 1999

This experiment was conducted to characterize the vertical transport trend of dissolved elements through throughfall, stemflow, effluent from Ao layer, and leachate out of soil profile on Pinus koraiensis stand in Experimental Forest of Kyunghee University, located in Kwangju, Kyunggi province for 12 months from July, 1998 to Jun, 1999. In addition, we investigated the content of dissolved elements and the factors influencing the water chemistry concentrations separately collected from the field. Water movement in the process of throughfall and stemflow from precipitation, and rainfall leached from Ao layer into soil water was governed by concentration of through fall, precipitation, rainfall intensity, seasonal variation, and other factors. Also, smaller changes of pH in soil water than that of dissolved elements in soil water could contribute buffer capacity, as well as balancing the concentration between cations and anions.

• Journal of Korean Society of Forest Science
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• v.74 no.1
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• pp.82-87
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• 1986

Noticed that large number of the Korean white pine (Pinus koraiensis S. et Z.) has lost its typical excurrent tree from by removal of apical shoot in the process of cone harvesting, the investigation and analysis for the species were made on the basis of the relationship among DBH, total height, merchantable height, and merchantable volume, compared with normally grown Japanese larch (Larix leptolepis Gordon). One hundred sample trees for each species were selected in the same aged stands for the study. Results have indicated that the pine has shown abnormal height growth pattern mainly by the disturbance of external artificial force. The pine's forked and/or crooked stems by the reason lave led the result of less merchantable volume in the same DBH classes. Consequently, the pine would have undesirable tree form in terms of timber production, unless free from apical shoot disturbances. Considered to the merit of the Korean white pine that can produce timber and pine nuts, management alternatives for the pine stand were suggested to achieve maximum rate of return for the silvicultural investment.

• Journal of Korea Foresty Energy
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• v.18 no.1
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• pp.1-5
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• 1999

Variations in the wood quality were analyzed to utilize Korean pine (Pinus koraiensis S. et Z.) efficiently and to develop suitable use, depending on the stem location. Variations in the tracheid length and width, microfibril angle, compression strength were measured at the heights of 0.3, 1.3, 2.3, and 5.3m in the longitudinal direction of the 20m pine and they were analyzed by Duncan`s multiple range test. Variations in the tracheid length, width and compression strength did not show significant difference, whereas those in the microfibril angle showed significant difference. However, the microfibril angle did not vary with the height of trees, showing inconsistent pattern in change.

• Journal of the Korean Wood Science and Technology
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• v.23 no.1
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• pp.28-34
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• 1995

Korean pine(Pinus koraiensis S. et Z.) is an economically important species in Korea because it will be harvested largely within next 20~30 years. The purpose of this study was to investigate changes in green moisture content, specific gravity and shrinkage in the stems of a Korean pine trees to provide fundamental information for technical processes. The followings are the results of this study. 1. There were about 110% differences in the heartwood and sapwood' green moisture contents (heartwood=59.5%; sapwood=170.6%). 2. There were no significant differences in average volumetric shrinkage between heratwood and sapwood, even though there were significant differences in moisture contents between them. Therefore, moisture content did not significantly influence on the shrinkage. 3. There was no significant relationship between height and shrinkage in heartwood. However, in the sapwood, shrinkage was highly correlated with the height. 4. Shrinkage levels were the most significant in south-bound direction and least significant in north-bound direction in both heartwood and sapwood. 5. There was a positive correlation between specific gravity and shrinkage in the sapwood. However, no such a relationship was found in the heartwood.

• Journal of the Korean Wood Science and Technology
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• v.42 no.1
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• pp.58-67
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• 2014

We investigated the mechanical properties of Korean red pine (Geumgangsong, Pinus densiflora forma erecta Uyeki) of Uljin province in Korea as a basic research to investigated the material properties. Compressive strength of Korean red pine was $36.2N/mm^2$, which was slightly lower than the pine (Pinus densiflora S. et Z.) in Korea. The compressive strength of Korean red pine showed the maximum value at a distance of 60 mm from the pith. Bending strength of Korean red pine was $76.5N/mm^2$, which was slightly higher than the pine (Pinus densiflora S. et. Z.) and nut pine (Pinus koraiensis) in Korea. Similar to the compressive strength, bending strength of Korean red pine showed the maximum value at a distance of 60 mm from the pith. On the other hand, the shearing strength showed the maximum value at part of including the pith. This result does not coincide with the results of compressive and bending strength, in consideration of the specific gravity, which is consistent. Surface hardness of Korean red pine was $43.7N/mm^2$ in cross section, $12.0N/mm^2$ in radial section and $13.7N/mm^2$ in tangential section respectively. The mechanical properties of Korean red pine were similar to the pine and nut pine having a similar specific gravity. The mechanical properties were greatly affected on the specific gravity than the annual ring width.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.379-382
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• 1991

Tree height at age 10 was used to estimate the statistical efficiencies of sampling size in the progeny test of Pinus koraiensis S. et Z. Experimental design was RCB design which consists of 25 half-sib families in each of three blocks. The number of families and blocks were fixed, therefore, the number of trees sampled per plot was the only factor that influences the environmental portion of the family mean height. Coefficient of variation, the estimate of the standard error of the family mean height, decreased with increase of sampling plot size, and became stable from 4-tree plot sampling (6.97%). The experimental error was significant from 7-tree sampling plot size. Nonlinear relationship (${\hat{Y}}=10.425e-^{0.073x}$ ; $R^2$=0.840) was found between the sampling plot size and the standard error of family mean height.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.19-23
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• 1983

Number of 1-year-old cone in Pinus koraiensis was influenced by the factors consisting of the tree form. Number of cones increased with increasing DBH, diameter, volume of crown and number of forked stems. However, tree height, crown length, and the ratio of crown diameter to crown length showed no significant relations with number of cones.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.562-570
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• 1998

This study was carried out to investigate the percentage of the net precipitation in Korean Pine(Pious koraiensis S. et Z.) stand separated by monthly, annually, the amount of rainfall and distance away from stem, at University of Sangji, Wonju, Kangwon province, during the period from April 1993 to October 1996. The average percentage of net precipitation showed 55.7% of the total precipitation, the minimum percentage of net precipitation was 45.7% in May and the maximum percentage was 62.9% in July. The average percentage of net precipitation at 0.3m far away from the stem showed 45.9% of the total precipitation and showed 60.3% at 0.6m distance. The average percentage of net precipitation within precipitation of 10mm and less showed 37.5% of tatoal precipitation and showed 70.9% within precipitation of 100mm and over. The relationship between percentage of through-fall and total precipitation were highly significant. It was estimated to be $Y_{(%)}=12.35LnX_{(mm)}+9.45$($R^2=0.735^{(**)}$). The relationship between stemflow and rainfall was estimated to be $Y_{({\ell})}=0.27X_{(mm)}-1.83$($R^2=0.921^{(**)}$). The relationship between percentage of net precipitation and total precipitation was estimated to be $Y_{(%)}=13.79LnX_{(mm)}+4.56$($R^2=0.946^{(**)}$) with significance at 1% level.