• Korean journal of applied entomology
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• v.59 no.4
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• pp.417-420
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• 2020

In this study, to grasp the current status of cone insects occurrence on Korean fir (Abies koreana) in Mt. Halla, 117 cones damaged by cone insects in three areas in Mt. Halla were collected and placed in growth chamber until adults emerged from the cones from August to October on 2019. And species and numbers of adults emerged from the cones were identified. Also proportion of cones damaged by cone insects was examined at four study plots in Mt. Halla. As a result, total 233, 101, and 4 adults of Dioryctria abietella (Denis & Schiffermüller), Cydia kamijoi Oku, and Scathophaga stercoraria (L.) were identified from 117 collected cones, respectively. The average number of emerged adults per cone was 1.99 for D. abietella and 0.86 for C. kamijoi. And the average damage rate of cone insects in four study plots of Mt. Halla ranged from 49.7-80.1 percent, with differences between regions. Also, our results show that positive correlation between the damage rate per tree and the number of cones per tree, and between number of emerged cone insects and the size of cones were found. It suggests that the cone insects prefer host trees with lots of cones per tree and with larger size of cones.

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.498-504
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• 1994

The damage by the black-tipped sawfly, Acantholyda posticalis posticalis Matsumura, has been incheasing at several locations in central part of the Korean peninsula. This study was undertaken at selected plots in locality of Kapyung-gun. Kyunggi Province from 1984 through 1987. The purpose of this study was to provide basic information for integrated control of this pest and to determine the economic threshold by investigating the pest-host interactions with special reference to damage analysis. The results obtained were as follows ; 1. One year old cone formation began to be reduced when 30-40% of the needles were destroyed. With 70% of defoliation, few cones were produced. 2. Number of two year old cone formation and amount of cones began to be reduced when 61-70% of the needles were destroyed ; economic threshold of the defoliation rate retarding the seed production was 51%. 3. Growth of the trees was significantly reduced when more than 50% of the needles were destroyed, and cone production began to be retarded at 30-40% of defoliation. Therefore, it was determined that the economic thresholds requiring the control practices to keep normal tree growth and cone production from being reduced were 50% and 30%, respectively.

• Landscaping Tree
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• s.93
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• pp.9-11
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• 2006

전국 어디서나 쉽게 볼 수 있는 참나무류는 가을이면 우리에게 정성스러운 열매를 도토리라는 정겨운 이름으로 우리에게 돌려준다. 그리고 우리 조상들의 예로부터 도토리를 슬기롭게 이용하여 와KT고, 야생동물의 긴요한 식량으로 사용되어, 자연을 풍요롭고 아름답게 만드는 슬기로운 산물이다. 자연을 표방하는 기획물 사진에는 다람쥐가 도토리를 먹고 있는 모습이 대표되는 한 장면이기도 하다. 우리나라 전국어디서나 신갈나무, 갈참나무, 떡갈나무, 굴참나무, 상수리나무, 졸참나무 등 많은 참나무류가 분포하여 가을이면 단풍의 극치를 이루기도 한다. 이들이 만들어내는 종자에 해충이 탐을 내어 우리의 정서를 빼앗고 있다 대표적인 것이 요즘 등산로나 산책로를 따라 가면 길 위에 많이 떨어져 있는 참나무류 가지들의 피해는 도토리거우벌레의 피해이다. 마치 톱으로 참나무가지를 잘라 떨어뜨리는 모습은 자연의 신비가 오묘하다는 것을 말해 주기도 한다. 구과에 알을 낳고는 가지를 주둥이로 잘라서 떨어뜨려 어린자식이 도토리를 먹고는 쉽게 땅속에서 들어갈 수 있게 하는 것이다. 참나무류 도토리를 직접 가해하는 몇몇 해충에 대한 생태 및 방제법을 간략하게 소개하고자 한다.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.93-96
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• 2006

In order to prevent cones from being damaged by cone insects, Gravitarmata margarotana and Dioryctria abietella, sprinkler system was installed on the Pinus koraiensis Seed Orchard. Such a test was conducted at Chung-ju, Chungcheong buk-do, Korea in 2002. Insectides of Diflubenzuron 25% WP ${\times}2,500$ and Cyfluthrin 2%EC ${\times}\;1,000$ were sprayed at fifteen-day and twenty-day intervals during the period of insects adult occurrence by sprinkler system. The Gravitarmata margarotana generally emerged for about 53 days from middle April to early June, and peak emergence was 10 days from April 20 to April 30. Dioryctria abietella generally emerged for about 108 days from late April to early August, and peak emergence was 10 days from May 20 to May 30. Damage rate of cones were $8.7{\sim}9.7%$ and $10.9{\sim}12.7%$ on average with crown insecticide spraying with Cyfluthrin and Diflubenzuron, while 67.5% when not treated. Control effectiveness of this insecticide spraying was $85.6{\sim}87.1%$ and 83.9%와 81.2%, respectively. When it considers the forest environment, it is recommended diflubenzuron which is low toxic pesticide. In conclusion, effectual times and number of diflubenzuron 25% WP application with sprinkler system against cone insects were from early May through late August and six times at twenty-day interval.

• Korean Journal of Agricultural Science
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• v.29 no.1
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• pp.32-43
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• 2002

The peach pyralid moth (Dichocrocis punctiferalis) is reported as import ant pest insect to chestnut fruits in Asia including Korea. For seasonal occurrence of D. punctiferalis in 1996, 1998 and 1999, D. punctiferalis adults were collected by light trap and sex pheromone wing trap in the chestnut orchard. Also, damaged rate of chestnut fruits were examined each collecting site. In 1996, according to examination by using light trap at three different site in Kongju, the occurrence peak of 2nd gene ration of D. punctiferalis adults was early August. Collected individuals after September were cons ide red as 3rd generation. Damaged rate due to maturation type was 26.5% averagely. The order of damaged rate were early, late and middle maturation type as 35.04%, 19.35% and 26.03%, respectively. Using synthetic sex pheromone trap at Kongju, Cheungyang and Buyeo in 1998, occurrence peaks were occurred mid-August to 2nd generation and late September to 3nd gene ration in Kongju. However, from early-August to late-September 5 peaks were occurred sequentially in Cheungyang. Second generation adults were occurred in mid-August and 3rd ones were occurred from late-September to early-October in Buyeo. In 1999, occurrence peaks of 3rd generation were early, middle and late September in Kongju, Cheungyang and Buyeo respectively. Damaged rate were 6.8%, 6.6% and 15.3% in Kongju, Cheungyang and Buyeo, respectively. Damaged rate order due to variety were Eunki, Chukpa, Danpa, Bokpa, Wangjung, Byunggo57, Yuoma at Buyeo and were Chukpa, Dukmyung, Byunggo57 at Cheungyang in 1999. Damage rate of chestnut were different with variety. Eunki and Chukpa in Buyeo and Chukpa and Dukmyung in Cheungyang were more damaged by D. punctiferalis respectively.