Green zones locating in factory sites offer habitats and resting space for many insects. Some of the insects invade into factory buildings and contaminate goods during manufacturing. Pest management in the green zones has been carried out with only pesticides and have not been done with the other methods. Then this study was conducted to control the number of insects in a green zone by changing the shapes of trees. Juniperus chinensis L., which is planted most frequently in the green zone, was used in this study and relationship between the shape of the tree and the number of flying insects captured on the tree. The shape was characterized with height of the tree, size of a space occupied by leaves and degree of crowding of leaves. Then this study revealed that the smaller the size of the space and the lower the degree of crowding of leaves, the fewer the number of flying insects on the tree. The height of the tree also effects on the number of flying insects.

These results indicate that changing the shape of trees is a useful method to control the flying insects in a green zone of a factory.

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It has been worried that warehouse beetle (Trogoderma variabile) and Khapra beetle (Trogoderma granarium) may invade with imported commodities and infestate in Japan. Pheromone baited traps have been used to monitor the presence of these stored product pests in U.S.A. We conducted to monitor insects with pheromone traps at 21 residential environments throughout Japan during summer in 1991. 2659 of Trogoderma sp. were captured. 96% of captured Trogoderma are T. varium, and 3.9% are T. inclusum. Orphinus sp. are captured too. It was proved that pheromone traps are excellent tool for monitoring Trogoderma sp. in Japan too and no infestation of warehouse beetle and Khapra beetle were observed.

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[in Japanese]

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[in Japanese]

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The "slit-trap" method was proved to be effective as attractant for the brown marmorated stink bugs, Halyomorpha mista. When several traps were set aroud the buildings, the number of bugs which invaded into dwellings was apparetly decreased.
The application of insecticide to window-frames was also carried out as a prior method to prevent the invation of the bugs. The prevention was almost perfect in case of ferro-concrete buildings such as hotels. In case of ordinary wooden houses, the number of the invading bugs was markedly decreased, though the prevention was not perfect.
The establishment of a completely effective method against the invation of the bugs into wooden houses is open for our future investigations.

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[in Japanese]

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Seasonal variations of the room temperature and relative humidity, dehumidifying effect by ventilation and efficacy of some air conditioner or dehumidifier were investigated in several residences, in relation to the environmental conditions for the house dust mites. Suitable periods of month for mite occurence seemed to be longer in concrete house than in wooden house, showing May to October and June to September, respectively, in the areas surveyed. Outdoor humidity in the time between two and four in the afternoon often showed below 60%, the threshold level of the mite occurence. This fact indicates that the ventilation such as by opening windows in these hours may be effective for decreasing the indoor humidity, while in other times, it may cause adverse effect to decrease indoor humidity. The efficacy of dehumidify of air conditioner or dehumidifier varied greately among the type of the products in the point of view of suppressing the mite population.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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