• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.165-168
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• 2011

An organic apple (Malus ${\times}$ domestics Borkh.) orchard was established to study the interaction effects of ground cover management systems (GMS) and nutrient sources (NS) on soil and tree nutrient status and tree growth. Trees received one of four GMS: 1) green compost (GC), 2) wood chips (WC), 3) shredded paper (SP), and 4) mow-and-blow (MB). Across all GMS, one of three NS was applied: A) a commercial organic fertilizer (CF), B) poultry litter (PL), and C) control (NF). Overall, GMS had greater effects on the variables than did NS. GC mulch supplied greater nutrients, followed by WC, SP, and MB mulches. SP trees had lower foliar [N] in the first two years than the GC and WC trees. GC-and WC-treated trees had larger trunk cross sectional area than the SP and MB trees.

• 한국약용작물학회:학술대회논문집
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• 2009.05a
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• pp.201-202
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• 2009

• Journal of Forest and Environmental Science
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• v.34 no.5
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• pp.376-381
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• 2018

For the control of oak wilt caused by Raffaelea quercus-mongolicae, an antifungal microorganism, Streptomyces blastmyceticus, was used as a potential agent. Culture suspension of S. blastmyceticus was injected into Quercus mongolicae in the research forest of Kangwon National University by $ChemJet^{(R)}$ trunk injection and Macro-infusion at root flare injection. $Alamo^{(R)}$ (a.i., propiconazole 14.5%), a fungicide currently used for the control of oak wilt in USA, was also treated by both methods to compare the efficacy. For preventive efficacy, culture suspension of the pathogen was inoculated at 1 month after injection of either agent. Tested trees were cut at 3 months after treatment, stained with 1% Fuchsin acid, and then non-conductive area (NCA) and re-isolation frequency (RIF) of oak wilt fungus were compared among treatments. While NCA was the highest as 47.3% in pathogen only treatment, it was the lowest as 16.0% in sterilized water treatment by Macro-infusion. NCAs of Alamo treatment by Macro-infusion and ChemJet injection were 25.3% and 32.1%, respectively. NCA of S.blastmyceticus treatment by ChemJet injection was 32.3%, similar with Alamo treatment's by ChemJet injection. All treatments by either injection method showed significantly lower NCA compared to the pathogen only treatment. These results indicate that S. blastmyceticus injection shows the preventive efficacy against oak wilt disease by suppressing the growth of pathogen injected. NCA of Macro-infusion injection of sterilized water was lower as 16.0%, compared to 21.3% of ChemJet injection. It means that Macro-infusion is more effective in translocation of sterilized water than ChemJet injection by even distribution. RIF from wood discs of treated trees showed high in pathogen only treatment, but relatively low in S. blastmyceticus treatment. RIF results were correlated with NCA results. From the above results, it was confirmed that S. blastmyceticus showed preventive efficacy against oak wilt disease by ChemJet trunk or Macro-infusion at root flare injection.

• Research in Plant Disease
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• v.26 no.1
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• pp.19-28
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• 2020

Jujube witches' broom (JWB) disease is a high-risk plant disease that occurred on and devastated jujube orchards throughout South Korea in the 1950s. Recently, as the jujube cultivation area has been significantly increased nationwide, we investigated the disease in jujube orchards in the Boeun region to obtain basic information for proactively evaluating the risk of JWB outbreaks from 2017 to 2019. A field trial was conducted to evaluate the effect of the trunk injection of Sungbocycline (a. i. oxytetracycline calcium alkyl trimethyl ammonium 17%, OTC). The incidence of JWB disease was very low in Boeun, but it was gradually increased mainly in the area and on the farms where it had occurred previously. The trunk injection with OTC was most effective in the early stages of growth. However, even though the trees were treated with OTC, disease symptoms appeared in other healthy branches in severely affected trees. When the tree was first injected with OTC in June, the control efficacy of second injection was higher one month after the first injection than five months. These results suggest that early diagnosis based on various symptoms and early control based on them can be very effective in preventing JWB disease in advance and increasing control efficacy.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.190-211
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• 2010

The purpose of this paper is to provide the preliminary data for maintenance of old trees of natural monuments and establishing protection projects. Accordingly, growth conditions, location circumstances, environment and protection management were analyzed for old trees at 34 sites in Gyeongsangbuk-do. Tree forms, crown, trunk and trees' health, leaves volume were analyzed in survey sites. As the results, the growth of Picrasma quassioides in Songsadong, Andong-si and Catalpa ovata in Hongwon-ri, Cheongsong-gun were not in good condition, along with other old trees of 6 cities (Quercus variabilis in Susan-ri, Uljin-gun, Juniperus chinensis in Hujeong-ri, Uljin-gun, Pyrus ussuriensis in Ssangjeon-ri, Uljin-gun, Salix glandulosa var. pilosa in Deokchon-ri, Cheongdo-gun, Pinus densiflora for. multicaulis in Hwasan-ri, Mungyeong-si, Pinus densiflora in Daeha-ri, Mungyeong-si). Accoding to these results, protection project and consistent monitoring are necessary. The analysis results of growth conditions per location circumstances showed that the old trees in the small spaces with large traffic of people were in bad condition. Therefore, it is necessary to secure sufficient space and soil improvement for such trees. The analysis results of growth conditions per species showed that Zelkova serrata, Quercus spp., Pinus densiflora are in good condition while Salix koreensis and others, i.e. a singular tree, are in poor condition. Thus, relatively smaller individuals and separately situated trees need careful management in their protection. The analysis results of trunk's growth ratio showed that Pinus densiflora, Ginkgo biloba, Zelkova serrata are in good condition whereas Juniperus chinensis, Quercus variabilis, Salix koreensis are not. It is a recent trend that tree surgeries are gradually decreasing; there are a number of damaged trees with no maintenance/management, and several sites requiring mend trunks management and cabling, bracing in protection and management projects. Hence, in the future, local government and management organizations should plan for systematic management and establish a protection plan for the natural monument trees. Also, 12 sites were found to be in need to purchase lands in order to secure the growth spaces, and since most of these areas are available for purchase, it is needed to promote a budget and purchase those areas through persuasion of the owner. These areas seems crucial in order to maximize the effect of conservation efforts and budgets for the preservation and restoration of the old trees.

• Korean Journal of Environment and Ecology
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• v.25 no.6
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• pp.893-902
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• 2011

The purpose of this study was to survey structures and growth conditions of Pinus densiflora village groves, and to establish management strategies for their desirable growth and conservation. Twelve village groves were selected in western Gangwon province for the study. The age of the study groves ranged from 50 to 200 years. Average dbh (diameter at breast height) and density of trees for each study grove were 27~52cm and 0.5~9.3 trees/$100m^2$, respectively. Soil environments were favorable to Pinus densiflora growth in the majority of the study groves, but 2 study groves with sandy soils showed considerably poor nutrient contents. Low tree vitality was found in some of the study groves due to poor conditions of root growth from soil fill and trampling. There were detachment of cambial tissue and damage of stem cavity at 6 study groves, which were caused by artificial injury, careless pruning, and frost damage. Light disease damage by Rhizosphaera kalkhoffii and phomopsis blight were found at 6 study groves. Light pest damage by Thecodiplosis japonensis was also found at 6 study groves, but the pest damage at 2 study groves was relatively considerable. Thus, major factors limiting normal growth of Pinus densiflora village groves were infertility, soil fill and trampling, stem damage, and disease and pest. Desirable management strategies were explored to solve growth-related problems and to conserve the study groves. The management strategies included fertilization of organic matter and lime, removal of soil fill, soil plowing and graveling, wood-trail installation or woodchip mulching, supply of wood fences and protective frames, surgical operation for damaged stems, vitality enhancement, and trunk injection to improve growth environments or control stem damage and disease/pest.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.4
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• pp.165-171
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• 2006

This is the research to prepare a purification program for relatively less polluted stream by using phytoremediation. We calculated a treatment amount of nutrients followed by growth of Helianthus annuus (a kind of sunflower), setting up the plant reactor in the hothouse. Moreover, to investigate a field applicability, we could find increased contents of nitrogen, carbon and hydrogen in plants by setting up a H. annuus planted artificial floating island in an irrigation canal. When we changed the dissolved inorganic nitrogen(DIN) concentration of the influent from 28.5 to 199.2 mg/l and the dissolved inorganic phosphorus(DIP) concentration of the influent from 13.3 to 25.4 mg/l, growth disorder has not appeared though it is much higher than the criterion of water for irrigation. In this case, the removal rate of DIN was $81.7\sim98.6%$, and that of DIP was $81.9\sim98.4%$ in 3 days stay on average. It has appeared that the efficient hydraulic retention time(HRT) was 48 hours. The following contents of nitrogen, carbon and hydrogen of H. annuus appeared in the artificial floating island: nitrogen was $3.2\sim7.8%$ in the trunk and $3.0\sim6.3%$ in the root. Carbon was $40.1\sim57.7%$ in the trunk and $43.4\sim53.8%$ in the root.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.276-282
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• 2017

Purpose: This paper presents the effects of soil drought stress during the growing season and pre-harvest period on tree growth and fruit quality of "Yumi" peach, an early season cultivar. Methods: Soil drought stresses were treated with four levels of -30, -50, -60, and -70 kPa during long term (LT) and short term (ST). For LT treatments, soil water was controlled for nine weeks from May 1 to July 5, which was assumed as the full growing season. For ST treatments, soil water was controlled for four weeks from June 10 to July 5, which was assumed as the pre-harvest season. Tree growth and leaf photosynthesis were measured, and fruit characteristics such as fruit weight and diameter, soluble solid and tannin contents, and harvest date were investigated. Results: Soil water deficit treatments caused a significant reduction in tree growth, leaf photosynthesis, and fruit enlargement. LT water stress over -60 kPa during the full growing season caused significant reduction in tree growth, including shoot length, trunk girth, leaf photosynthesis, and fruit enlargement. ST water stress over -60 kPa during the pre-harvest period also induced significant reduction in leaf photosynthesis and fruit enlargement, while tree growth was not reduced. In terms of fruit quality, water stress over -50 kPa significantly reduced fruit weight, increased soluble solid and tannin contents, and delayed harvest time in both LT and ST treatments. Conclusions: As a result, it is assumed that LT water stress over -60 kPa can reduce both tree growth and fruit enlargement, whereas ST water stress over -50 kPa can reduce fruit enlargement without reducing tree growth. From an agricultural perspective, moderate water deficit like -50 kPa treatments could have positive effects, such increased fruit soluble solid contents along with minimal reduction in fruit size.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.149-159
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• 2017

There are many studies on the health and protection of Old-growth and Giant Trees, concentrating on empirical judgment and basic protection measures. The problem this study addresses is the relative importance and priority of the health evaluation indicators of Old-growth and Giant Trees. Firstly, this study exports the evaluation indicators of Old-growth and Giant Trees. The evaluation system for the degree of danger of Old-growth and Giant Trees are composed of two layers: 5 fields and 46 indicators. Secondly, using the AHP and PCA method can determine the weight of each field and each index factor. The process of AHP establishes the relative importance judgment matrix of each field and fully proves that the main cause of danger is individual aging. The PCA method suggested that trunk rot status, light conditions, tree surgeries, bacterial diseases, and soil moisture level are the most important factors in each field. These aspects should be given priority in the management and protection of Old-growth and Giant Trees. Weight values obtained in this study seemed to be useful in the evaluation of Old-growth and Giant Trees.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.618-629
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• 2009

The objective of this study was to examine the impact of pruning (P treatment) and transplanting (T treatment) of Acer palmatum on cambial growth and compartmentalization of pruning wounds for one year after treatments. Changes of cambial electrical resistance (CER), sizes of pruning wounds, cambial growth of trunks and stems near the wounds, and total phenols at branch unions during the period were examined using a total of 49 trees. After harvesting, areas of discolored wood behind the wounds, relative proportions of extractives, holocellulose and lignin at branch unions were also determined. CER and the cambial growth of trunk at 30 cm above the ground (TGR) were inversely correlated, and differences of CER and TGR among three treatments were significant. TGRs of control, P treatment and P+T treatment after the treatments were 112.2%, 72.4% and 52.5% of the annual growth for the year before the treatments, respectively. The cambial growth rate of stem (SGR) at 1.5 cm above the branch bark ridge and the closure rate of pruning wound (WCR) for one year after treatments were positively correlated, and WCR of P treatment of 39.8% was significantly higher than that of P+T treatment of 31.8%. Wounds of P+T treatment formed greater discolored area per unit area of pruning wound (D/W Ratio) than those of P treatment significantly. Lower WCR and higher D/W Ratio of P+T treatment suggested less ability of compartmentalizing the wounds than P treatment. Total phenols at branch core of pruning wound for both treatments heightened a month after treatment, and then lowered. The contents at below core of the wound were higher than those at control ones continuously, while they became similar each other at above core. Relatively high phenol contents of the extractives at P+T treatment implied that trees with P+T treatment allocated more energy to compartmentalize their wounds. Holocellulose and lignin contents at the branch core of treated branch unions of both treatments were lower and higher, respectively, than at the same part of the union with living branch, as results of the tree reaction to protection from wounding and microbial invasion.