• Research in Plant Disease
• /
• v.11 no.2
• /
• pp.208-212
• /
• 2005

At the survey of June, 2002, total 294 dead frees were found in 20 ha of Black pine (Pinus thunbergii) forest located in the western coastal region of Korean peninsula. The dead trees were scattered over the 27 place as groups of about ten trees each. As a result of the field survey on the relationship between the conditions of dead trees and the occurrence of fruiting bodies of Rhizina undulata around the dead and/or dying trees, from June 2002 to August 2004 in the four plots, the occurrence of infected trees was observed as a shape of an irregular concentric circle from the first infected tree and R. undulata was found mainly around the dead tree. Because there was no observation of any other insects and pathogens which would kill trees, the cause of tree death in groups was considered owing to R. undulata. From the analysis of the physical and chemical proper ties of the soil collected from the damaged areas, the pH of soil was between 4.6 and 5.8 and the contents of soil nutrients were very low. Any "fire" trace was not found at all the 27 damaged places in the area, Taean, Chungcheongnam-Do, which are generally known as an important factor to initiate development of the disease. Therefore, further examination is needed to verify precisely about other environmental factors related with the group dying of the Black pines in this area beside 'fire'.

• Korean journal of applied entomology
• /
• v.45 no.3 s.144
• /
• pp.371-373
• /
• 2006

Life history of Ivela auripes (Lepidoptera: Lymantriidae), a pest of Cornus controversa, was investigated both in laboratory and field condition. At $24{\pm}1^{\circ}C$, developmental period from larvae to adult and adult life span was $26.3{\pm}0.3$ and $4.4{\pm}0.2$ days, respectively. Developmental period of pupae reared in the laboratory was not significantly different from those collected in the field. Female moths reared in the laboratory laid significantly less eggs than those emerged from the pupae collected in the field. Light trap catches was less effective than direct monitoring in the field. The two monitoring results showed that adult moth emerged from early June to late June, and the time of 50% cumulative emergence was 17 June.

• Korean journal of applied entomology
• /
• v.48 no.4
• /
• pp.447-451
• /
• 2009

Locust gall midge (LGM), Obolodiplosis robiniae (Haldeman) (Diptera: Cecidomyiidae), is a cecidomyiid insect forming roll-up galls on leaves of Robinia pseudoacacia Linnaeus (Fabaceae). LGM, known as native to North America, was reported from Korea and Japan in 2002. LGM was observed weekly or biweekly to clarify their voltinism and distribution within the crown of the host tree in two sites of Osan and Siheung in Korea from May to August, 2007. Density of LGM was investigated based on the number of larvae per leaf. Two generations of LGM were observed in Siheung site whereas three generations in Osan site during the present study. The result indicated that LGM had at maximum three generations per year. The density of LGM in Osan was higher in the upper crown of the host trees than middle or lower part. In Siheung, LGMs were distributed more on the exterior of the lower crown than the interior. The average number of larvae per gall was $3.3{\pm}0.1$ and $2.8{\pm}0.1$ individuals per leaf in Osan and Siheung, respectively.

• 한국균학회소식:학술대회논문집
• /
• 2006.10a
• /
• pp.10-12
• /
• 2006

• Research in Plant Disease
• /
• v.15 no.1
• /
• pp.13-16
• /
• 2009

In April 2008, cherry (Prunus yedoensis Matsumura) in Jeju exhibited severe disease of branches forming numerous twigs. Five isolates from diseased leaves were identified as Taphrina wiesneri on the basis of biological and genetic characteristics. Twenty one commercial fungicides were tested for control of the disease in vitro. Of the 21 fungicides, triazole compounds (difenoconazole, propiconazole and tebuconazole) showed relatively good antimicrobial activities. Results from the planta bioassays indicated that triazole compounds reduced the witches' broom disease showing control value $25.7{\sim}52.8%$ compared with the nontreated controls.

• The Plant Pathology Journal
• /
• v.28 no.3
• /
• pp.311-316
• /
• 2012

Fusarium root disease can be a serious problem in forest and conservation nurseries in the western United States. Fusarium inoculum is commonly found in most container and bareroot nurseries on healthy and diseased seedlings, in nursery soils, and on conifer seeds. Fusarium spp. within the F. oxysporum species complex have been recognized as pathogens for more than a century, but attempts to distinguish virulence by correlating morphological characteristics with results of pathogenicity tests were unsuccessful. Recent molecular characterization and pathogenicity tests, however, revealed that selected isolates of F. oxysporum are benign on Douglas-fir (Pseudotsuga menziesii) seedlings. Other morphologically indistinguishable isolates, which can be virulent, were identified as F. commune, a recently described species. In a replicated greenhouse study, inoculating Douglas-fir seedlings with one isolate of F. oxysporum prevented expression of disease caused by a virulent isolate of F. commune. Moreover, seedling survival and growth was unaffected by the presence of the F. oxysporum isolate, and this isolate yielded better biological control than a commercial formulation of Bacillus subtilis. These results demonstrate that an isolate of nonpathogenic F. oxysporum can effectively reduce Fusarium root disease of Douglas-fir caused by F. commune under nursery settings, and this biological control approach has potential for further development.

• Journal of Digital Contents Society
• /
• v.18 no.1
• /
• pp.191-195
• /
• 2017

In this study, a smartphone application for reporting trees infected with pine wilt disease was developed to prevent the spread of the disease by the disease-carrying pests/insects, which is most damning to the country's pine trees, South Korea's representative tree species, and to ensure the sustained maintenance of the country's forest trees. Such application for handling information on the infected pine trees has three key components, as shown below. (1) Explanation of the pine wilt disease pests/insects, (2) Image capture of the infected pine tree, and transmission of its GPS location, (3) Inquiry on the neighboring area infected with pine wilt disease. It is possible to promptly provide the spatial information of the areas infected with pine wilt disease by developing a dedicated application for reporting trees infected with the disease based on GPS information. If users participate actively in the application and integration with the forest service application is to be realized, the application would be more actively utilized.

• Journal of Forest and Environmental Science
• /
• v.28 no.2
• /
• pp.97-105
• /
• 2012

A Gangwon region consisting of over 80% of forest area has industries that have been developed by utilizing its clean region image. However, the recent climate change has increased the forest disease & insect pest as well as the forest fire and the major cause is known to be the increase in the frequency of a drought occurrence. From the aspect of climate change, it can be said that drought and forest are important in every aspect of the adaptation and mitigation of climate change measure as they increase forest disease & insect pest that leads to desolation of usable forest resource. In addition, the increase of forest fire reduces resources that can absorb greenhouse gas, which leads to increase in green house emission. The purpose of this study is to provide a motive for concentrating administrative power for protecting forest in a Gangwon region by selecting a drought management needed local government through a drought forecast according to the climate change scenario of a Gangwon region.

• Journal of Korean Society of Forest Science
• /
• v.97 no.5
• /
• pp.555-558
• /
• 2008

Trapping efficiency of various sex pheromone blends of the peach pyralid moth, Dichocrocis punctiferalis was compared by field study to develop monitoring system with its sex pheromone at chestnut orchards in Korea. Five candidates of the sex pheromone blends used for the field trapping of D. punctiferalis males were 70:30, 75:25, 80:20, 85:15 and 90:10 mixture of (E)-10-hexadecenyl aldehyde (E10-16:Al) and (Z)-10-hexadecenyl aldehyde (Z10-16:Al). All lures were treated with 1 or 2 mg of each blends. During 2 years of field survey, the 75:25 blend was usually the most effective in attracting males among 5 blends tested. For the 2nd generation, the best capturing activity for D. punctiferalis male was observed by lure with 75:25 blend. Both 90:10 and 75:25 blends showed highest efficiency for the 3rd generation. In most cases. lures treated with 1 mg of blend caught more male moths than these treated with 2 mg of blend.

• Journal of People, Plants, and Environment
• /
• v.24 no.3
• /
• pp.301-309
• /
• 2021

Background and objective: The purpose of this study is to analyze the case of healing experience for lifestyle and environmental diseases through life and activities in the forest from the perspecitive of critical realism, and how the causal power and mechanism of the healing experience relate to forest healing factors and programs. Methods: 93 video data of people who started living in the forest for disease treatment were analyzed using a qualitative content analysis method from the perspective of critical realism. Categories for analysis include general categories (age, duration, occupation, disease name), forest therapy categories (climate therapy, plant therapy, water therapy, diet therapy, kinesiotherapy, psychotherapy), and other categories (ecology, learning and management, life tools), etc., and the unit of analysis is the context unit. Results: 1) The diseases that motivated life in the forest were digestive system diseases, lung diseases, cardiovascular diseases, endocrine system diseases, and various lifestyle-related diseases and environmental diseases in similar proportions. This indicates that forest life does not have specificity to respond to specific diseases, but provides treatment and recovery for all lifestyle and environmental diseases. 2) Among the forest therapies, climate therapy and plant therapy are related to the climatic and residential environment in the forest where 'natural persons' live. And others such as water therapy, diet therapy, kinesiotherapy, psychotherapy indicate the change from the lifestyle that caused the disease to the lifestyle for treatment and recovery. Conclusion: Life and activities in the forest provide an environment for treatment and recovery in which the healing principles such as aromatherapy, nutritional and dietary therapy, kinesiotherapy, and emotional psychotherapy are integrated in the 'real world'.