In the late fall of 1961, the writer carried out a field test of vole control by telodrin, which is a new insecticide and rodenticide, at the foot of Mt. Yatsugatake in Nagano Prefecture, an area of high land in central Honshu.
First, the mark and release method was applied to Microtus montebelli in an area of 1 ha on the grassy land. It was estimated that 45 voles inhabited the area. Many voles were recaptured at the same traps, showing a tendency to affect the resident voles, but some of them moved 10_??_20m in one night, and the greatest distance reached was
30m.
Second, telodrin was tested with three kinds of preparations as follows:
1. 400 cc of 15% telodrin emulsion diluted with 181 of water, and 600_??_700cc of the preparation were sprayed on the ground of 1.5m in diameter at intervals of 10m, and it was done at 50 spots in 0.5 ha of the area.
2. 100_??_120 g of 0.5% telodrin powder previously preparared, were scattered on the ground of 1. 5m in diameter at intervals of 10m, and it was done at 25 spots in 0.25 ha of the area.
3. 100_??_120g of 2% telodrin powder previously preparared, were scattered in the same manner as in the case of the 0.5% powder.
The recapture work after the poisoning was conducted from the following night to third night; then the percentage of the reduction of the Microtus population was estimated as 90% in the emulsion plot and in the 0.5%, powder plot, and 100% in the 2% powder plot.
It is considered from this field test that the sporadic scattering of telodrin at ten-meter intervals yields almost the same results as with the scattering of endrin on the whole surface.

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From the standpoint of statics, it may be said, that, in a logging cable-way, the hauling rope acts on the carriage to make increase the tension of the track cable or to bear some parts of the carriage load. These effects of hauling rope are often represented by a load coefficient to carriage load. In this report, the authors mathemati-cally derived some formulas to give the load coefficient in a cableway, which carries a single or multiple loads along a span, and also sugested aproximate formulas for practical use.

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This report deals with the rooting from the cuttings of young slash pine (Pinus elliottii ENGELM. var. elliottii) in different beds and the influence of hormone treatment (IBA) on them. The aim of this experiment is to obtain the good rooting seedlings (T/R ratio is as possible as small) by cutting.
(A) Rooting of cutting of young slash pine seedlings in different soil beds
The object of this study is to obtain the good root system of the cuttings in the nursery. The young seedlings of slash pine were cut off on the ground into two parts, that is the upper part (Tops) and the under parts (Roots). The upper parts were plant-ed in the following four different plots as cutting's beds and the T/R ratio of the cuttings of each bed were investigated in 90 days after plantation and is compared with the T/R ratio of the seedlings which were brought up in the nursery bed in succession without cutting.
The T/R ratios of the beds of experimental plots are shown as follows:
Plot Kind of bed Percolation rate T/R ratio cc/min.
5 mins. 15 mins.
Plot A Red soil from Kyoto 3cc 3cc 3.07
Plot B **Block soil A horizon from Tokyo 67 65 2.19
Plot C Sand from Tokyo 140 110 1.30
Plot D **Black soil B horizon from Tokyo 89 87 2.16
Plot E **Black soil (Control) 89 87 5.33
(1) The seedlings by cutting in A_??_D have smaller T/R ratios than the seedlings in E which were grown normally in the nursery bed, and have comparatively rich root system in comparison with their growth as shown in photos 2_??_6.
(2) While the rooting percentage, the length and the weight of top of the cuttings increase in un-proportion to the parcolation rate of the bedding soil, the T/R ratio of them becomes smaller in proportion to the percolation rate.
(3) It will be necessary further experiments whether these seedlings obtained by the cuttings are more favourable or not than the ordinary seedlings in their following growth.
(B) Rooting of young slash pine cuttings by hormone treatment
Generally speaking, the most of Pinus species are difficult for cutting, therefore this experiment was carried out about the influence of IBA hormone treatment on the rooting of cuttings of young slash pine seedlings with comparatively easy rooting.
Results obtained in 90 days after the treatment are shown below:
(1) All the cuttings of control plots showed the longer adventitious roots from the bottom of them.
(2) In the case of treatment with 500 ppm IBA, the percentage of the rooted cutt-ings decreased in proportion to the length of the time of treatment, and all the cuttings died in the 24 hours treatment.
(3) Only, in the case of treatment with 500 ppm IBA, some of the cuttings rooted not only from the bottom, but also from the close parts to the bottom. But, the length of their roots were shorter (cf. Phot. 7).

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According to the result of the observations on the effect of the fungicide, CuCO₃, Cu₃(ASO₄)₂, Cu₃(AsO₃)₂, CuSO₄, ZnCl₂, ZnSO₄, NaF and HgCl₂, upon the mycelial growth of four species of brown rot fungi, G. abietinum (BULL. ex FR.) KARST., G. trabeum (PERS. ex FR.) MURR., G. subferrugineum (BERG.) BOND. et SING. and G. sepiarium (WULF. ex FR.) KARST., HgCl₂ showed the strongest effect on checking the mycelial growth, Cu₃(AsO₃)₂, Cu₃(AsO₄)₂, NaF, ZnCl₂, CuSO₄, ZnSO₄ came next and CuCO₃ was the weakest. Writer also found that G. trabeum had the strongest resistance for these eight chemicals, G. subferrugineum and G. sepiarium came next, and G. abietinum was the weakest.

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