• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.4
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• pp.82-89
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• 2003

This study was carried out to find the suitable root-ball size for the planting construction of landscape trees. Surveyed trees for this study were Cercidiphyllum japonicum and Prunus yedoensis, and the root-ball size was classified into 3D, 4D, 5D, and 6D(D meaning the diameter at the base of a tree). Visual ratings on a scale of 1 to 9 were used as a means for measuring the regrowth strength after planting tested trees. Test trees with 3, 4, 5 and 6D root-ball size were planted on March. 16, 2002 and visual ratings were measured up to April. 30, 2003. Cercidiphyllum japonicum and Prunus yedoensis started showing a difference in regrowth by each rootball size a month after planting. The regrowth quality of Cercidiphyllum japonicum was low at 3D, medium at 4∼5D and high at 6D root-ball size, while the regrowth quality of Prunus yedoensis was low at 3∼4D and medium-high at 5∼6D root-ball size. According to the above results, a root-ball size for good regrowth quality was a little bit different between Cercidiphyllum japonicum and Prunus yedoensis. 4D of Cercidiphyllum japonicum and 5D of Prunus yedoensis could be guidelines for root-ball diameters at the base of trees when planting. However, we concluded that 4D∼5D root-ball is the optimum guideline for regrowth when adapting this guideline to all landscape trees with 8∼l0cm diameter at the base.

• Journal of Korean Society of Forest Science
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• v.95 no.3
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• pp.240-249
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• 2006

Recently, dispersion of damaged forest by pine wilt disease has been regarded as a serious social issue. Damages by pine wilt disease have been spreaded by natural area expansion of the vectors in the damaged area, while the national wide damage spread has induced by human-involved carrying infected trees out of damaged area. In this study, damaged trees were detected and located on the digital map by aerial photograph and terrestrial surveys. The spatial distribution pattern of damaged trees, and the relationship of spatial distribution of damaged trees and some geomorphological factors were geostatistically analysed. Finally, we maked natural spread pattern map of pine wilt disease using geostatistical CART(Classification and Regression Trees) model. This study verified that geostatistical analysis and CART model are useful tools for understanding spatial distribution and natural spread pattern of pine wilt diseases.

• Journal of Environmental Science International
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• v.25 no.12
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• pp.1689-1699
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• 2016

The growth conditions of planted trees, invasion of nuisance herbaceous species, competition between species, and effects of erosion control were monitored over five years in a riparian greenspace in Gapyeong County that was established through multilayered and grouped ecological planting. Of 156 trees planted in the upper and middle layers, 5.8% died. This tree death was attributed to poor drainage or aeration in the rooting zone from the clay-added root ball and too deep planting as well as a small-sized root ball and scanty fine roots. Of all the trees, 21.6% grew poorly due to transplant stress in the first year after planting, but they started to grow vigorously in the third year. This good growth was largely associated with soil improvement before planting, selection of appropriate tree species based on growth ground, and control of dryness and invasive climbing plants through surface mulching and multilayered/grouped planting. Mixed planting of fast-growing species as temporary trees was desirable for accelerating planting effect and increasing planting density. Thinning of fast-growing trees was required in the fifth year after planting to avoid considerable competition with target species. To reduce the invasion of herbaceous and climbing plants that oppress normal growth of planted trees, higher density planting of trees (crown opening of about 15%), woodchip mulching to a 10-cm depth, and edge planting 2 m wide were more effective than lower density planting (crown opening of 70%), no surface mulching, and no edge planting, respectively. This reduction effect was especially great during the first three years after planting. Nuisance herbaceous plants rarely invaded higher density planting with woodchip mulching over the five years. Higher density planting or woodchip mulching also showed much greater erosion control through rainfall interception and buffering than lower density planting with no mulching did. Based on these results, desirable planting and management strategies are suggested to improve the functions of riparian greenspaces.

• Plant Resources
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• v.6 no.2
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• pp.120-128
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• 2003

The objectives of this study, an analysis of the variation for leaf and fruit characteristics among the selected ten populations of Sorbus commixta Hedl. could be used for the conservation of gene resources and could provide information to superior trees selection. The results obtained from this study can be summarized as follows; Approximately, the Mt. Sungin population at Ulleung island showed larger values in overall characteristics and populations. On the other hand, Mt. Halla population at Jeju island showed the smaller values of the overall characteristics and populations. ANOV A tests showed that there were statistically significant differences in all leaf characteristics among the populations as well as individual trees within populations. But, for fruit characteristics, differences were statistically significant only among the populations. Cluster analysis using single linkage method based on leaf and fruit characteristics showed that ten selected populations of S. commixta in Korea could be clustered into three groups. Group I is Mt. Sungin at Ulleung island, Group II is Mt. Halla at Jeju island, and Group III comprises Osan, Mt. Kaji, Mt. Duckyoo, Mt. Balwang, Mt. Sobaek, Mt. O-dae, Mt. Jiri, and Mt. Taebaek. The selection level based on major agronomic traits, which are the Number of Fruit per Fruiting Lateral(NFL) over 50, and Fruit Length(FL) and Width(FW) over 10 mm, and Weight of 100 Fruit(WFI00) over 66 g, was applied on 100 sample trees, and five trees were selected. The selection effects from selected trees in NFL, FL, FW, and WF100 were evaluated as 132%, 151 %, 142%, and 264% compared to the mean of those 100 sample trees, respectively. Especially, Ulleung 2 showed excellent values that NFL and WFI00 were 95, and 69 g, respectively, suggesting a promising new cultivar for larger fruit and high productivity.

• Journal of Environmental Science International
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• v.13 no.10
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• pp.883-890
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• 2004

The purpose of this study is to survey and analyze the growth, management and surrounding environment of the big and old trees in Kyoungju-si or the cultural assets alive in our history, and thereby, provide for some data useful to their reasonable protection and use of their surrounding areas. As a result of surveying the growth conditions of the big and old trees, it was found that the height of new grass was 10.5cm on average, the activity scale of the wood was 7.2k$\Omega$, the soil hardness was $16.7kg/cm^2$, the soil acidity was pH 4.8, and the soil moisture was $13.3\%$. Such findings suggest that the soil has been acidified by people's frequent passages, but that the other growth conditions are more or less normal. Hence, it is desirable to secure a sufficient space around the trees or reduce people's stamping pressure with some mechanisms. On the other hand, the visible conditions of the trees were found more or less normal, but many trees remained cut or barked (with some cavities), requiring an optimal treatment or measure. Lastly, as the population has decreased in the suburban traditional villages, the surrounding environment seems to be less vulnerable to people's frequent visits. Nevertheless, in consideration of the fact that there are only a few public space for the villagers, it is deemed necessary to rearrange or maintain some parts of the surrounding environment as public space for villagers or hikers.

• The Korean Journal of Ecology
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• v.18 no.1
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• pp.189-201
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• 1995

In order to clarify regeneration processes and mechanisms of the disturbed Pinus densiflora forest, responses of Pinus densiflora to gap formed by disturbance were analysed by growth of saplings and mature and growth equations were obtained from branch growth of mature trees and height growth of saplings, and age distribution of saplings and young trees recruited within gap was analysed in relation to gap age. Height growth of saplings within gaps was accelerated after gap formation. Such abrupt increases of growth of saplings after the gap formation might be resulted in the difference of growth of saplings between gap and non-gap areas. In fact, height and diameter of saplings in the central part of gap were larger than those of saplings in marginal parts of gap and non-gap area. However, density of saplings was not different in both parts. In addition, growth of annual rings of mature trees bordering on gap also increased after gap formation. Branch growth of mature trees bodering on gap was 6.3 - 6.5 cm /year and the mean radius of gaps created by death of only one canopy tree was about 3 m. Therefore, for those gaps to be closed by branch growth it will take 46 years. Growth of saplings within gap showed exponential equation. Fifty years will be required for the saplings to enter the forest canopy by the exponential growth equation. Therefore, gap created by only one tree might be closed by branch growth of surrounding canopy trees in advance of being done by height growth of saplings. But gaps created by death of trees more than 2 will be closed by the growth of saplings. Among the regenerating saplings and young trees within gaps, individuals established in advance of gap formation were more than those established after the gap formation. From these results, it was assumed that the disturbed Pinus densiflora forests in these sites were regenerated by height growth of saplings recruited in advance of gap formation.

• Journal of Korean Society of Forest Science
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• v.7 no.1
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• pp.45-49
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• 1968

This experiment was carried out to study moisture contents including in the woody parts of standing Pitch Pine trees. The moisture measuring samples were made from the parts of root, branch, top, sapwood and heartwood of test trees. The test trees and average moisture contents measured from the parts of trees are as table (1) and (2). According to the results this study may be concluded as followings. 1) In the winter felled Pitch Pine trees highest moisture contents are shown in the top wood but lowest in the heartwood among the parts of tree. 2) In comparing moisture contents showing between two parts of tree, significant differences are show between top or heartwood and other parts but between branch or sapwood and root are not shown. 3) As general there is no significant variation in moisture contents of root, sapwood and heartwood among the test trees but branch wood is shown considerable variation.

• Journal of Ecology and Environment
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• v.43 no.3
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• pp.320-331
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• 2019

Background: Dioecious plant species having both male and female plants have been investigated regarding sex-related characteristics such as sex ratio, sex-differential resource requirements, and spatial segregation of the sexes. Habitat loss and fragmentation are major threats to the survival of plant populations, but dioecious species are particularly more prone to such habitat degradation than non-dioecious species because of their dimorphic sexual system. We examined the sex-related demographics of two Ilex cornuta populations being different regarding land use history. Methods: During 2016-2017, we examined I. cornuta trees with a basal diameter ${\geq}1.5cm$ in the Yongsu-ri population (YS population) and the Gotjawal Provincial Park population (GP population). Plant sex (male, female, or unsexed) was identified. The tree size (basal diameter and height of the main stem), clonal production (the ramet numbers per genet), and vitality for each clone were measured. The associations between population, sex, tree size, clonal production, and vitality were examined using ANOVAs and contingency table analyses. Finally, point pattern analyses using O-ring statistics were conducted to assess spatial patterns. Results: Upon excluding unsexed trees, the YS population with 74 trees was significantly male-biased (0.66), while the GP population with only 26 trees had a 1:1 sex ratio. In both populations, males and females did not differ in tree size. Although the mean number of ramets differed significantly between populations, females tended to produce more ramets than males. The proportion of weak trees was significantly higher in the YS than in the GP population. Neither population showed evidence of spatial segregation of the sexes. Conclusions: The two populations of dioecious I. cornuta are characterized by the small number of trees and relatively high frequencies of non-reproductive trees. Both indicate that these populations are quite susceptible to environmental and genetic stochasticity. On the other hand, the differences between populations in sex ratio, clonal production, and vitality suggest that conservation efforts for I. cornuta need to be population-specific. In order to help recover and enable this vulnerable species to persist, it is necessary to find ways to enhance their sexual reproduction and simultaneously reduce habitat disturbances due to anthropogenic activities.

• Journal of Forest and Environmental Science
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• v.38 no.3
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• pp.174-183
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• 2022

The study aims to examine population indices of mature trees in Jebel Elgarrie forest, Blue Nile State, Sudan. We used remote sensing techniques to stratify the forest into vegetation classes depending on tree density. We distributed 97 circular sample plots (0.1 ha) proportionally to the area of the vegetation classes. In each sample plot we identified, counted and recorded all mature trees (DBH ≥10 cm). We calculated frequency, density, abundance, richness, evenness and diversity for each species and we drew abundance rank curve of mature trees. We used One-Way ANOVA to test for differences (α=0.05) in mean density (No./ha) of mature trees between vegetation classes. Results revealed that the forest was conveniently sub-divided into high density (C1), medium density (C2), low density (C3) and bare farm land (C4) classes. We identified fifteen tree species that belong to 10 families and 14 genera. Combretaceae and Fabaceae were the common families while Anogeissus leiocarpa was the most frequently occurring species. While species diversity varied between vegetation classes, diversity of the forest as a whole is low. While mean density of mature trees in C1, C2, C3 and C4 it was 100, 74, 10, and 0, respectively, it was 54 for the whole forest indicating low stocking, Following One-Way ANOVA, multiple comparisons revealed significant differences in mean density of mature trees between C1 & C3 and C2 & C3. The study provided empirical results on population indices of mature tree species, which would be of importance for successful management and conservation of the forest.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.1
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• pp.12-26
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• 2010

This study was conducted to investigate current states and management of the protected trees in Gangwon-do. There were 701 protected trees in 42 species designated by 2008, which were distributed at 425 places. Major species were Zelkova serrata(29%), Pinus densiflora(24%), Ulmus davidiana var. japonica(11%), and Ginkgo biloba(5%). The protected trees played various roles in the villages, mostly as sacred trees(43%). The 51% of protected trees were 300 years or more in age, the 53% were more than 20 m in height, and the 57% were more than 300 cm in girth at breast height. The 69% of the protected trees have been designated for protection in 1982 and the rest have been designated by the local cities by 2008. The species number of the protected trees in Youngseo region was greater than that of the Youngdong region. The major species were Zelkova serrata (33%) and Pinus densiflora(17%) in Youngseo region, and were Pinus densiflora (38%) and Zelkova serrata(19%) in Youngdong region. The ratio of native species to exotic species was 33:1 in Youngseo region, and were 25:6 in Youngdong region. The 29% of protected trees were located in the field, 28% in the mountain, and 25% in the villages. The 45% of the ground were covered by herbaceous plants, 39% exposed, and 10% gravel mulch. Most of the protected trees had good growing conditions. The 70% of the protected trees were under good maintenance, and the rest were under undesirable conditions. The soil characteristics of the protected tree areas in Gangwon-do were not much different from those of Korean average. It seemed to be necessary to increase designation of protected trees based on the tradition, history, local value and academic application in Gangwon-do. In addition, it is desirable to suggest plans to utilize and manage protected tree areas for enhancing the value of natural heritages in Gangwon-do.