• Journal of Ecology and Environment
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• v.31 no.4
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• pp.341-344
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• 2008

We investigated the responses of red squirrels to pine nuts (Pinus koraiensis) treated with Lithium Chloride (LiCl) and the potential of the chemical for inducing conditioned taste aversion (CTA) in red squirrels. In red squirrels, nut feeding declined dramatically during the first 4 days after feeding with LiCl-treated nuts. The ratio of LiCl-treated nuts eaten to total nuts eaten declined from the $1^{st}$ day in LC-1 and the $2^{nd}$ day in LC-2, along with a general reduction in quantity eaten. Thus, feeding with LiCl-treated nuts induced CTA from the 2nd day after feeding, and CTA remained constant until the $4^{th}$ day, but disappeared on the $5^{th}$ day. The squirrels ate an average of $757.0{\pm}106.1mg$ (n = 2, range $682.0\sim832.0$) of LiCl before dying on the $16^{th}$ day of the study. The lethal dose of LiCl was 2.32 mg LiCl/g body weight, and the average amount of LiCl needed to induce CTA was $23.0{\pm}4.24mg$ (20 mg in LC-1 and 26 mg in LC-2).

• Journal of Korean Society of Forest Science
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• v.37 no.1
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• pp.61-63
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• 1978

Both bark and wood sections obtained, by cutting with a razor blade, from living tissue of Cronartium ribicola cankers of Korean white pine (Pinus koraiensis) were transferred to a mixture of 2 parts of chloroform and 1 part of methanol, and the sections were stained using a modified lactophenol cotton blue. The formula for this staining is as follows: Lactic acid 20gm, phenol crystal 20gm, cotton blue 0.05gm, and 60% EtOH 100ml. The rust hyphae and haustoria were stained blue, and the wide hyphae with straight or curved haustoria could be distingwished from the pine tissue.

• Journal of Korean Society of Forest Science
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• v.50 no.1
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• pp.72-73
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• 1980

The spermagonial state of Cronartium ribicola J. C. Fisher appeared on the discolored bark of Korean pine (Pinus koraiensis Sieb. & Zucc.) from late August through middle of October in Korea. A large number of ellipsoid or ovoid spermatia were contained in the spermagonial exudates that appeared on the bark of infected trees. In the spring (April-May) following the appearance of spermagonia, aecia broke through that part of the bark which had been occupied by spermagonia the year before.

• 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.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.842-846
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• 2004

To elucidate quality changes of pine nuts and walnuts coated with green tea extract-containing protein film during storage, pine nuts and walnuts were coated with soy protein isolate (SPI) and zein film containing green tea extract, and stored at $35^{\circ}C$ for 4 weeks. During storage, peroxide, acid, and 2-thiobarbituric acid (TBA) values increased with increasing storage time regardless of treatments. Degrees of lipid oxidation were lowest in protein coating containing green tea extract, followed by protein coating and control. After 4 weeks, for pine nuts, 40, 32, and 21% of peroxide, acid, and TBA values respectively decreased by treatment of zein film coating containing green tea extract compared with control. For walnuts, 29, 24, and 21% of peroxide, acid, and TBA values respectively decreased. With SPI film coating, 41, 36, and 8% of peroxide, acid, and TBA values of pine nuts respectively decreased. For walnuts, 26, 28, and 5% of peroxide, acid, and TBA values respectively decreased by treatment of SPI film coating containing green tea extract.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.225-230
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• 2009

Using dynamic programming, which is one of operations research techniques, the best pathway was chosen to maximize the total harvest volume for a Korean white pine (Pinus koraiensis) stand. This study was carried out in an age class III at Chuncheon National Forest, Gangwon province. That stand was assumed to apply 3 different thinning intensities of none, 30% and 50% thinnings. These thinning pathways are planned to implement two times, of thinning at 35 age and 55 age. The final cutting (rotation age) is assumed to carry out in 70 years. A growth function for Korean white pine stand was developed with forest inventory data, the volume was calculated with this growth function. As a result, the best thinning pathway for this Korean white pine stand using dynamic programming is to implement 30% at the first thinning and 50%at the second thinning.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.165-169
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• 2010

Fusarium circinatum is the causal agent of the pine disease commonly referred to as pitch canker. In this study, F. circinatum was isolated from the diseased Pinus rigida in the golf courses, Korea. The morphological characteristics and the molecular features of the isolates were investigated to identify the pathogen. Histone H3 gene and IGS rDNA region was analyzed and consequently the isolates identified as F. circinatum. All of them have the same sequences and the mating type was determined as MAT1-1. The inhibitory effect of the methanol extracts from the disease resistant pine species, Pinus koraiensis and Pinus densiflora and a susceptible species, P. rigida were evaluated against the isolate, F. circinatum. As a result, the extracts of P. koraiensis and P. densiflora showed higher antifungal activity than that of the susceptible, P. rigida.

• Journal of Korea Foresty Energy
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• v.21 no.1
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• pp.7-15
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• 2002

The essential oil free needles, which were left after distillation of essential oil from various coniferous needles, were fermented with food waste organics in order to use as compost and roughage. Microorganisms for the fermentation were selected from domestic sources such as swine compost, bark compost, and kimchi, etc, and consisted of aerothermophilic bacteria and actinomycetes. The weight reduction ratio of food waste organics treated with the microorganisms was 90% after 30 days treatment, and the fermentation temperature was kept at approximately $45^{\circ}C$. The compost process was really slow due to chemical compounds derived from needles, and it finally took 60 days for complete compost. When 10% of needle compost was mixed with soil for radish growth, the growth indicators such as leaf length and root weight were increased compared with control, while root weight, root width, and root length were inhibited on the addition of 20% needle compost. The nutrient value and digestibility ratio of various essential oil free needles as roughage for ruminant animals were evaluated. The ratio of crude protein for essential oil free needles from Korean pine(Pinus koraiensis) was 10.02%, which was higher than those of rice straw(5.48%) and corn(9.00%). The digestibility ratios of essential oil free needles from Sawara cypress(Chamaecwaris pislfera), Korean pine(Pinus koraiensis), and Japanese Red Pine(Pinus densiflora) was 53%, 34%, 34%, respectively, indicating that those essential oil free needles were considered as excellent roughage.

• 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.103-109
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• 1999

This study was carried out to investigate spectral characterisistics and chlorophyll contents of Pinus koraiensis needles in Gwangju-gun, Kyunggi-do. In spectrum analysis by each age, needle showed difference on 700∼1,100 nm(NIR : near infrared ray). Light reflexibility keeps constant between 1st year needle and 3rd year needle, current year needle's value was higher than others and that was higher for 400∼500 nm and 600∼700 nm at 550 nm. Transmission to needle's age showed the highest result in current year needle. It showed in order of current, 1st, 2nd and 3rd year needle at 550 nm and 750 nm. Especially, current year needles of Pinus koraiensis showed a tendency to change transmission coefficient in NIR. The result of transmission coefficient measurement by each position of slope showed in order of middle slope, upper slope and lower slope. But the gathered needle in middle slope made marked change at NIR. Chlorophyll a content of the upper slope's needles was higher than other 4 positions but a component ratio was lower. In needle of the oppressed tree, Chlorophyll a content was rather low than others. Chlorophyll a content by slope positions, the upper slope's needle showed a highest value(4.48 mg/g) and lower slope was lowest value(1.35 mg/g). Chlorophyll b content also showed a similar tendency to chlorophyll a and chlorophyll(a+b) contents.