• Korean Journal of Agricultural and Forest Meteorology
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• 제7권4호
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• pp.258-264
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• 2005

The objectives of this study were to study 1) emergence of pine bark beetles, 2) larval density in residual timber on Idlest land by each felling season, and 3) the secondary damage rates in the tended forest. Pine forest land which had undergone tending had a higher secondary damage ratio $(59.6\%)$ by pine bark beetles than forest land that was not tended $(2.8\%)$. The number of escape holes averaged 11.3 0.31 per $250 cm^2$ on the bark of leaf trees in the tended forest. The number of escape holes was higher in the Jinju site than in the Hamyang site. The larval habitat density of pine bark beetles as compared with each felling period was higher after mid-October than in forests tended early in October. Thus, forests should be tended before early October in order to prevent secondary damage from pine bark beetles. Secondary damage in the tended forest was higher in the upper part $(75.5\%)$ of the tree crown than in the lower part $(49.2\%)$. The damage was higher in terminal shoots $(80\%)$ than in lateral shoots $(48\%)$. Therefore, secondary damage by pine bark beetles can cause deterioration of the elongation growth of the forest trees. In conclusion, if by-products of tended pine forest forests are neglected, they will be utilized as a propagation site for pine bark beetles (Blastophagus piniperda L). The propagated adults will damage the tender shoots of the leaf trees and thus seriously limittheir elongation.

• Journal of Forest and Environmental Science
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• 제13권1호
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• pp.66-80
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• 1997

Pinus koraiensis is one of the major speciese which have been recently planted for ten years and consists of 31% of total plantation. Presently young stand less than 30 years consists of 87% of total forest, but tending thinning of it is hardly carried out and the desirable direction for the thinning is not established yet. The objective of the study is to introduce the optimum thinning plan and thinning method through the long-run experiment of tending thinning for the Pinus koraiensis stand. The experiments carry out to interprete its growth model on the subject of two thinning experimental plots and yield table of Pinus koraiensis. As the basic step for understanding the thinning process, a theoretical growth model which is suitable to express the growth process is required. For that purpose, three growth functions (Mitscherlich, 4 parameter Richards, 3 parameter Richards) are applied to the diameter growth of the sample trees which are taken in the two plots. The results show that 3 parameter Richards is the most suitable. It is also verified that the diameter growth, the height growth, and the decrease in the number of stocks can be estimated by this function. To estimate the growth change of single tree, growth model including parameter h which is related to the occupation area of single tree are introduced. The parameter h can be estimated by using the data of the diameter growth obtained from the established experimental plots. Therefore, if both verification and modification of the usefulness of the model suggested is made, equations which tell about the thinning effects could be drived by estimating the growth process of single tree in advance.

• Journal of Korean Society of Forest Science
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• 제99권4호
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• pp.625-632
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• 2010

This study was carried out to analyze the yarding productivity and cost of the man-power operation by plastic chute, the yarding operation by yarder attached in tractor (Chuncheon Tower-yarder) and yarding operation by Tower-yarder (RME-300T) in forest tending operation. As result of average yarding timber volume was 0.67 $m^3$, 3.8 $m^3$ and 7.3 $m^3$ per day and man, respectively. And, when an yarding timber volume was 60 $m^3$/ha, the total yarding time including setting up and dismantling time of the plastic chute and yarding line was 20 days and 2 hours, 7 days and 1 hours and 21 minutes, 3 days and 4 hours and 27 minutes, respectively. The operation costs were 104,448 won/$m^3$, 29,968 won/$m^3$ and 23,032 won/$m^3$, respectively. And, when yarding timber volume was 60 $m^3$/ha, the total operation cost including setting up and dismantling time of the plastic chute and yarding line was 7,429,173 won/ha, 2,431,573 won/ha and 1,610,672 won/ha, respectively.

• The Korean Journal of Mycology
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• 제45권1호
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• pp.1-13
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• 2017

Armillaria species are non-obligate root pathogens, as well as facultative parasites. The genus consists of about 40 species with worldwide distribution that are difficult to identify morphologically. Their hosts include conifers, hardwoods, vines, and even herbs. These fungi contribute to natural thinning and succession of vegetation in forests and decompose wood to develop edible fruiting bodies from spring to autumn. Its genets have a lifespan of up to 2000 years and have been found to occupy as much as 960 ha of forest land. Recently, forest tending work such as thinning of forests has resulted in the creation of tree stumps that support the growth of Armillaria, and these mushrooms have become an income source in mountainous areas. Therefore, identification of these species is needed. We review the difficulties in identification, suggest a species identification key for Korean indigenous species, and discuss the significance of Armillaria in terms of forest ecology and plant pathology.

• Journal of Korean Society of Forest Science
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• 제101권3호
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• pp.526-537
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• 2012

The study was carried out to classify forest vegetation structure of Mt. Guryong which is located in Bonghwa-gun, Gyeongsangbuk-do province. 72 plots(quadrat) were investigated from July to August in 2010 using phytosociological analysis methodology of Z-M schools. The forest vegetation of the study area was classified as Quercus mongolica community group that was further divided into 5 communities; Pinus densiflora for. erecta community, Acer mono community, Quercus mongolica typical community, Larix leptolepis community and Pinus koraiensis community. Pinus densiflora for. erecta community was subdivided into Quercus variabilis group and Pinus densiflora for. erecta typical group. Acer mono community was also subdivided into Prunus maackii group and Deutzia glabrata group. The vegetation of the study areas could be described as 1 community group, 5 communities and 4 groups and 7 units in total. Classified vegetation units were highly correlated with altitude and topography. It was considered that forest tending operations for maintaining need to be continuously practiced for Quercus spp. with highly relative dominance value in the Pinus densiflora for. erecta community (vegetation units 1, 2).

• Journal of Forest and Environmental Science
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• 제21권1호
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• pp.75-82
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• 2005

The experimental study was carried out to evaluate the performance of underplanted Pinus koraiensis 2-2 seedlings in the closed canopy natural deciduous forest. Overstory density effects on seedling survival and growth were assessed 7 years after underplanting. Seedling survival rate was 80%, average height was 0.9m with minimum of 0.3m and maximum of 2.1m, and average diameter at butt end was 1.7cm with minimum of 1.4cm and maximum of 3.5cm. Compared with the growth rate of the pine plantation after clearcutting, the growth performance of underplanted pine seedlings was so poor that the height growth was less than 30% and diameter growth was less than 20%. Even though the Pinus koraiensis seedlings would be shade tolerant, the establishment and performance of underplanted Pinus koraiensis seedlings could be promoted by more than 50% of canopy regulation that provide adequate light at the forest floor and should exhibit a strong positive response following overstory removal by tending operation.

• Journal of Korean Society of Forest Science
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• 제90권3호
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• pp.388-397
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• 2001

In forestry, where improvement of labor environment is quite impossible, improved posture would result in direct effects by preventing waste of physical strength, prevention of accidental injury caused by fatigue accumulated on certain body parts, and prevention of human error by inattentiveness due to weakened body. Therefore, this research carried on analysis of working posture in manual forest work(thinning using chain-saw, salvage cutting using chain-saw, clearing using hand saw, clearance of twiner using sickle, pruning using saw with a long handle, and tending of young growth using sickle) using OWAS analysis system. According to the OWAS method, percentage of OWAS action categories III and IV in the tasks using chain-saw and sickle was higher than another tasks. For the compared middle skillful worker group and low skillful worker group at felling work using chain-saw, percentage of OWAS action categories IV in middle skillful worker group was 5.1%, and low skillful worker group was 14.1%.

• Journal of Korean Society of Forest Science
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• 제95권6호
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• pp.729-734
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• 2006

This paper aimed to suggest decision-making method for forest management planning using integer programming. Thus, the study examined 85 stands consisting of Korean pine, Japanese larch and oak stands-all of which were at the most suitable time for tending, selection thinning, commercial thinning and final cutting-in the experimental forest of Kangwon National University. The forest management model comprised one objective function, maximizing harvest volume in each stand according to tree species and the kinds of practices, and seven constraints: frequency and stands of practices, minimum and maximum yields, even yields, maximum production, and decision-making varialbes. Besides, the entire period intended by the study was 10 years, divided into 5 management periods. In conclusion, the forest management planning model using integer programming proved that among 85 stands, forest practices were conducted over 68 stands (202.8 ha), producing the total harveted volume of $20,000m^3$, while the rest was reserved. This case study could help make decisions on whether and when the forest practices and harvests could be done in a specific condition.

• Journal of Korean Society of Forest Science
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• 제89권2호
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• pp.185-197
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• 2000

This study was carried out to research structure of forest vegetation and site condition, and supply basic data for conservation of pine forest and ecologically sustainable forest management and control in Anmyondo area. The forest of Anmyondo were largely classified as four forest community : Pinus densiflora community, Pinus thunbergii community, Pinus rigida community, and Quercus variabilis community. Organic matter, total nitrogen, and other nutrients in soil of the study area were relatively low, and average soil pH was 4.9. Soil texture was sandy clay or heavy clay and so the aeration and permeability could be poor. In this study site, the methods such as the promotion of germination of pine seeds through removal of forest floor and inducement of natural regeneration through such method as regeneration under shelter wood would be better than the method such as afforestation after clear-cutting for conservation the pine forests. Also, it will be a good method to practice tending for hardwood species in the dominant areas by hardwood species.

• Journal of Korean Society of Forest Science
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• 제102권2호
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• pp.170-175
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• 2013

This study was conducted to investigate the effect on the habitation of Monochamus alternatus, a vector insect of Pine wood nematode by the tended sound stumps for the developing forestry control methods of Pine wilt disease controls. Field cage plots (1 m ${\times}$ 1 m ${\times}$ 1 m) were established 12 units (Experiment1:4 units, Experiment2:8 Units) and were treated 4 kinds(February in 2010, February, April, June in 2011). The adults of M. alternatus were put into 4~5couples each the cage June in 2011. Presence or absence of the larva entrance holes and larva were detailed November in 2011. The larva were appeared in the sound stumps of sapling and young trees tended at February, April, June, the current emergence year of M. alternatus, but were not appeared in the sound stumps of sapling and young trees tended February in 2010, one year before the emergence of M. alternatus. The larva habitated in stumps of sapling were likely to be smaller in size in compare to the larva in stumps of young trees. In case of young tree, the larva were found at the cleft part of bark, but were not found at ridge part of bark. All observed larva appeared at part of bark and between the bark and the woody parts, but were not found at the woody parts. To develop the control guiding principal of sound stump after forest tending practice, further experiment need is in existence oviposition and larvae of vectors by height of stemps.