• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.24-24
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• 2018

Degraded plantation forests are increasing because of unfavorable forestry conditions prevailing in Japan, including falling timber prices, increasing operational costs, and aging and declining forestry workforce. To remedy this situation, appropriate management strategy is required. This study introduces the challenges of Odai Town, Mie Prefecture that employed a new management strategy by evaluating site suitability for conifer forests and that proposes a new forest management regime of planting deciduous trees in unsuitable sites. The site suitability for conifer forests was evaluated from two aspects: the natural site conditions and the relationship among site conditions, growth, and damage by Anaglyptus subfasciatus Pic. in Cryptomeria japonica D. Don and Chamaecyparis obtusa Sieb. Et Zucc. forests. By analyzing the relationship among site conditions, growth, and insect damage based on field data obtained in plantation forests, growth evaluation and insect damage evaluation maps were developed. Based on the natural forest investigation, natural site condition maps for C. japonica and C. obtusa were established. Furthermore, by integrating these evaluation maps with the forest road maps showing the accessibility to the forest, the forest management regime for the whole plantation area of Odai Town was established. The forest management regime map indicates the sites suitable for forestry: suitable for long-rotation, short-rotation, and potential sites for short-rotation. The sites unsuitable for forestry were considered to be more suitable for broadleaved forests. Clear-cutting was conducted in a small area and different seral stage saplings (approximately 20 deciduous tree species) suitable to the site conditions were planted in an area of $80-120m^2$ protected by deer-fences. This might establish a forest composed of many species with a multilayer vertical forest structure in a short period. The planted saplings were distributed neither randomly nor uniformly to reflect the natural distribution of trees in the forest. A challenge to develop new products using the deciduous trees has started, such as wood chips for preparing smoked food, essential oil, and deodorizer. As these challenges have just begun, their effects on enhancing sustainable resource management are still being monitored. Even with the challenges, this regime can be of high value as a management strategy to remedy the situation of expansion of degraded forests in Japan.

• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.122-127
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• 2022

Agroforestry in terms of intercropping cow pea as summer forage with Grewia tenax was undertaken under sub -irrigation system in two consecutive seasons of 2017 and 2018 in saline soil of Khartoum State of Sudan. The aims were to find out suitable agro forestry system for saline soils as well as to investigate effect of tree spacing on field summer forage crop under semi -irrigation system. Therefore G. tenax trees that spaced at 4×4 m were used as main factor versus cow pea crop that incorporated at 25×50 cm intervals by using completely randomized block design with 3 replications. Trees and crop parameters were determined in terms of plant growth and yield. In addition to land equivalent ratio and soil chemical and physical properties at different layers were determined. The results revealed that, soil parameters in terms of CaCo₃, SAR, ESP, pH paste and EC ds/m were increased with increasing soil depths. Meanwhile tree growth did not show any significant differences in the first season in 2017. Whereas in the second season in 2018 tree growth namely; tree height, tree collar and canopy diameters were higher under intercropping than in sole trees. Cow pea plant height recorded significant differences under sole crop in the first season in 2017. Unlike the forage fresh yield that was significant under the inter cropped plots. Tree fruit yield was higher under sole trees and land equivalent ratio was more advantageous under GS2 (1.5 m) which amounted to 4. Therefore it is possible to introduce this agroforestry system under saline soils to provide summer forage of highly nutritive value to feed animals and to increase farmers' income as far as to halt desertification and to sequester carbon.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.345-352
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• 1998

A Korean endemic and evergreen small tree ' Dendropanax morbifera $L_{EV}$.(Araliaceae)' is a component of evergreen forest and mainly idstributein sourthern region and islands in Korea. A local population of D. morbifera which is located between evergreen and deciduous forest within 50m x 50m quadrate was investigated to ascertain the change of population structure, emergence and growth dynamics of seedlings and saplings, and pattern of spatial distribution by the temproal and spatial expansion of population . The result of analysis of population structure by Importnace Value(IV), evergreen forest showed a high species diversity of evergreen tree species such as Cinnamomum japonicum, Machilus japonica, Neolitsea serica, Daphniphyllum macropodum, Ligustrum japonicum, and etc, in middle and under story than in upper story where Camelia japonica and Quercus acuta were dominant. And in conterminous deciduous fores, the major component of evergreen forest in this region, Camellia japonica, Quercus acuta, evergreen tree of Lauraceae and etc. were abundant in only under story. IV of D. morbifera differed from among three story. In comparative analysis of emergence and growth dynamics of D. morbifera seedlings and saplings between evergreen and deciduous forest, emergece and density of seedlings were significantly greater in evergreen than in deciduous forest, and growth of height and basal diameter of seedlings and saplings were slightly larger in evergreen than in deciduous forest. The spatial distribution patterns by Moristia's index mapping of indivuduals using a lattice method of XY axis within this population showed that seedlings(age up to 2 years) and saplings (age>2 years and height<1m) both evergreen and deciduous forest were more or less aggregated apart from mature trees, and thougth intermediate trees(height>1m and dbh<10cm) had a aggregated distribution pattern, mature trees(dbh>10cm were uniform. In conclusion , the expansion of D. morbfera population from evergreen to deciduous forest accompanied with a mumber of evergreen woody species, and also, emergence and recruitment, and growth of seedlings were greatly influenced moisture and canopy by around community structure.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.352-357
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• 2001

This experiment was carried out in order to develop some chip budding techniques related to the production of high quality maiden apple trees. Optimum chip budding time for apple trees appeared to be from mid-August to early September. Untying wrapping tapes after 6 8 weeks from budding led to higher graft success and better shoot growth than removing the tapes earlier or later than the 6-8 weeks. Dipping pre-cut bud chips into ordinary water of $25^{\circ}C$ for 5 hours did not hamper the graft-success nor the early season growth of the graft compared with non-treated control. Dipping the pre-cut bud-chips into the $35^{\circ}C$ water for 3 hours or for 5 hours hampered the union formation and shoot growth of the 'Fuji' apple trees.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.6 s.113
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• pp.78-89
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• 2006

This study was conducted to analyze the planting structure and ecological characteristics of greon spaces on the grounds of e Dangjin steam power plant. To achieve these goals, we surveyed existing vegetation, plant community structure, Plant volume and growth rate. Based on e vegetation analysis, existing vegetation was classified into six types: herbaceous species $(70.54\%)$, evergreen coniferous trees $(21.17\%)$, deciduous broad-leaved trees $(5.10\%)$, deciduous coniferous trees $(1.47\%)$, shrubs $(0.12\%)$, and other types $(1.59\%)$. The coal storage, office, and playground areas were community is the natural forest area where a Pinus thunbergii / Pinus densiflora community is distributed in terms of vegetation structure, species diversity, plant volume, and growth rate. The artificial green spaces(near the coal storage, office, playground areas) had a single-layer structure. Species diversity indices of the artificial green areas were $0.1655\~0.4807$ compared to 0.8628 in the natural forest, which presented a good growth environment. Also, the plant volume in the artificial green space was lower than that of the natural green space. Therefore, it would be desirable to develope a multi-layer structure similar to that of the vegetation in the natural green space in order to improve the amount of plant volume. The plant-damage ratio of Pinus thunbergii was $52.48\%$ in the coal storage area, and $8.48\~ 11.52\%$, in the other survey areas. Also, the vitality of Pinus thunbergii was $15.45k{\Omega}$ in the coal storage areas, which indicates bad growing conditions. This suggests that soil characteristics and dust have a bad impact on growth. The investigation into deciduous tres' growth status showed that appropriate plants would be Albizzia julibrissin, Acer palmatum var. sanguineum, Acer palmatum, Malus spp., Prunus sargentii.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.155-163
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• 2003

In order to analyze the succession process from a pine forest to an oak forest, the tree growth of Pinus densiflora and Quercus mongolica ssp. crispula was monitored in a permanent quadrat for 23 years. The measurements were carried out for the stem diameter (DBH) of Pinus densiflora between 1977 and 1999 and for the height of Quercus mongolica ssp. crispula saplings between 1998 and 2000. The floristic composition and the locations of the individual P. densiflora and Q. mongolica ssp. crispula trees and saplings in the quadrat were recorded. P densiflora and Q. mongolica ssp. crispula individuals were randomly distributed within the quadrat. The relative growth rates (RGR) of DBH in P. densiflora were 0.085 $yr^{-1}$ for large trees and 0.056 $yr^{-1}$ for small trees in 1977. The RGR of height for Q. mongolica ssp. crispula was 0.122 $yr^{-1}$. The growth curve for DBH of P. densiflora was approximated by the logistic equation: $$DBH(t) = 30 {[1+1.16exp(-0.13 t)]}^{-1}$$ where DBH (t) the DBH (cm) in year t and t is the number of years since 1977. The growth in height of P. densiflora and Q. mongolica ssp. crispula was described by following equations: $$H (t) = 20.2 {[1+0.407exp(-0.137 t)]}^{-1} (P. densiflora)$$ $$H (t) = 30 {[1+20.7exp(-0.122 t)}^{-1} (Q. mongolica ssp. crispula)$$ Where H (t) is the tree height (m) in year t and t is the number of years since 1977 in P. densiflora and 1998 in Q. mongolica ssp. crispula. With these equations we predicted that the height of Q. mongolica ssp. crispula increases from 2 m in 1999 to 20 m in 2029. Therefore, Q. mongolica ssp. crispula and P. densiflora will be approximately the same height in 2029. The years required for succession from a pine forest to an oak forest are expected 33 with the range between 23 and 44 years.

• Journal of Forest and Environmental Science
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• v.33 no.1
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• pp.74-77
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• 2017

The purpose of this study is to analyze the effect of thinning intensity on the growth of large diameter trees in Korean white pine (Pinus koraiensis S. et Z.) plantation. Eight thinning plots were analyzed by categorizing into heavy thinning, light thinning, no thinning (control) according to thinning intensity. As a result, average DBH increased more in heavy thinning plots than in light thinning or unthinned plots. The number of large trees (DBH>25 cm) were obviously shown the most in heavy thinning plots. It is considered that heavy thinning is needed for the production of the large diameter trees.

• The Korean Journal of Ecology
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• v.13 no.4
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• pp.331-342
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• 1990

Analysis of vegetation on the pavements and under the trees of streets in Seoul city were investigated from July to November 1989. All of the vascular herbs were 9 orders, 13 families, 30 genera, 37 species and 1 forma. Species diversity and evenness index were higher on the pavements than under the trees of streets. Eragrostis multicaulis with C-4 pathway was a dominant species, and next orders of importace values were Eleusine indica(C-4), Digitaria sanguinalis(C-4), Taraxacum officinale(C-3) and Erigeron annus(C-3). On the pavements and under the trees of streets, light intensity and surface temperature were very high, Also, these sites were affected by many kinds of human interferences. Therefore, it was an example of adaptation to specific ecological environments that C-4 plats were more dominant than C-3, growth forms of C-3 plants were rosette or prostrate, and annual or biennial plants were distributed in these studied sites. Generally, fruits types were grains, achens and capsules. Seeds were very small and some had appendages such as pappus.

• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.499-508
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• 2019

The study was carried out to investigate growth of 48.6-L pot-cultivated 1-year-old 'Fuji'/M.9 apple trees depending on different levels of nitrogen concentration. While rise in tree growth was paralleled with increase of nitrogen concentration, more than 32 mM of nitrogen rather restrained tree growth. In particular, growth of 16 mM of nitrogen treated trees was satisfied with criteria for production of high-quality pot-cultivated nursery stocks. Although mineral contents of leaves were higher in 8 and 16 mM nitrogen treatments than commonly recommended mineral contents in apple orchards, such somewhat surplus minerals could be helpful for tree growth after transplanting to apple orchards. In addition, our result indicated that soils of 8 and 16 mM of nitrogen treated pots met appropriate criteria for soil chemical property of apple orchards. Thus, in the light of tree growth, mineral contents of leaves, and soil chemical property in the pots, 16 mM of nitrogen treatment is considered to be suitable for production of 1-year-old 'Fuji'/M.9 apple potted trees.

• 전기의세계
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• v.26 no.2
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• pp.57-65
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• 1977

In roder to investigate the influence of treeing on electric breakdown of solid organic insulator the initiation and growing mechanism of tree itself, and the correlation between corona discharge and treeing phenomena in solid orgainc insulating materials, several experiments were carried out by means of needle test on polymethyl-methacrylate. The obtained results showed that the existence of voids in specimen had important effects on initiation voltage of trees and, when the direct voltage was applied, the initiation voltage of trees increased by space charge effect. And also the stagnation phenomena due to the transfer of vacancy cluster or polymekr cage in specimen might beconsidered in process of growth of trees, and corona discharge seemed to be the pre-phenomena of treeing because trees were normally initiated by internal discharge in voids.