With the objects to make clear the way of controlling certain May beetles whose adults do not feed on turf grass but whose larvae do so, and also to make clear the cause of outbreak of the cupreous chafer in upland fields in Shizuoka prefecture, the author reared the adult insects with the leaves of certain food plants which are planted in the Hamamatsu seaside golf club and in its outbreak area, and measured the mortality of them, the number of non-fed insects and the amount of fed leaf, and thus investigated the control method using these obtained results.
(1) The adult insects took preferably 7 species of plants and their mortality was very low in the duration of rearing. These plants were Vitis vinifera L. (grape vine), Rhododendron pukhrum Sweet, Polygonum Blumei Meisn., Podocarpus macrophylla D. Don, Salix chaenomeloides Kimura, Ligustrum japonicum Thunb., Acacia Baileyana F. Mueller. Such plants as Mollissima Acacia Willd., Prunus Persica Batsch. (peach), Saccharum officinarum L. (sweet potato), Zoysia japonica Steud. could not rear them. It was thought that Triadica sebifera Small, Morus bombycis Koidz. (mulberry) and Citrus Unshiu Marcov. (mandarin orange) were not suitable for rearing them.
(2) The amount of fed leaf was greatest when Polygonum Blumei was given them : Vitis vinifera, Podocarpus macrophylla, Rhododendron pulchrum, Acacia Baileyana, Salix chaenomeloides, Ligustrum japonicum, Triadica sebifera, Citrus Un shiu, follow it, if arranged in the numerical order.
And its reason seems to be that the individuals feeding on Polygonum Blumei until the starting of rearing experiment were used as the test insects. In the average amount of fed leaf, the value of Podocarpus macrophylla showed larger than that of Vitis vinifera, and it was thought that its leaf is the most suitable for the rearing of this insects, and the distribution of that tree was very remarkably in outbreak areas.
(3) In case of the suitable leaf as the feed of the adult insects, the tendencies were observed that the amount of fed leaf for one day was almost constantly large through the rearing period, or increases with progress of the period. In cases of Triadia sebifera and Citrus Unshiu, these tendencies decreased. In cases of Mollissima Acacia, Morus bombycis, Prunus Persica and Saccharum officinarum which could not reared, it was recognized that they feed on those plants in small quantities. But they did not feed on Zoysia japonica.
(4) The May beetle that was the most injurious to turfgrass was such as Anomala schönfeldti Ohaus whose adult insects and larvae both could feed on turf grass and increase. The damage produced by such as the cupreous chaf er whose adult insects cannot feed on turf grass was very little in turf grass garden, and its damage area in turfgrass was limited to the place where the food plants of adult insects were distributed. In the place which has a large area of turfgrass as a golf course, the conception of Ecological Control, that the food plants of adult insects should not be planted, must be introduced for the control of this insect. And in this place, it seems that the control of adult insects was more effective than that of larvae.
(5) As the main reason why the larvae of cupreous chaf ers grow in great numbers in the upland fields of sweet potatoes and peanuts in west Shiyuoka prefecture, it was considered that the food plants fo their adult insects increased rapidely there. And in these districts, as the control of their larvae is carried on, that of adult nsects must be carried out too.

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1. This paper describes the results of field study concerning to the fire of turf grasses planted on the slopes and median strips of the Tokyo-Nagoya Expressway and some analyses between causes of fire and climatic conditions.
2. The number of fires has been increasing with year. This might be due to the increase of traffic volume with time.
3. The fires might be caused mostly by the cigarettes thrown away by drivers and occupants, but this is not firmly validated yet.
4. The occurrence of fires is closely related to the climatic conditions such as exposure to the sun, precipitation and humidity. All these conditions are reduced to the degree of moisture content of the turf grass itself.

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[in Japanese]

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