In this report, the author investigated the growth of red pine infested formerly with pine caterpillar and Sugi leaf-beetle, and estimated the progress of its damages.
The localities on the research were following three:
(1) Near Kazan Astronomical Observatory at Higashiyama in Kyoto City
(2) Tanabe-cho in Kyoto Prefecture
(3) Yamashina in Kyoto City
The first and the second were red pine stands which had suffered heavily damage by pine caterpillar, and at the third locality red pine has been damaged by Sugi leaf-beetle. These investigations were carried out in July (the third), October (the first) and December (the second) of 1961. Each part of stem, branch and needle was measured in weight, and the meterials for the stem analysis were gathered.
1. At Higashiyama, the growth of red pine injured heavily was not amounted to 30% of the presumed growth based on the growth of non-damaged tree. In this locality, it was found that many pine caterpillars had ingested red pine in July of 1956. Therefore, damaged trees had a smaller growth from 1955 to 1958, but on and after 1958 its growth has been gradually approaching to the normal.
2. The investigated red pine forest at Tanabe was 38_??_43-years old, and closed nearly. Its mean DBH was 8.5cm, and mean height was 7.7m. It is known that red pines were infested with a great number of pine caterpillars in 1955. In consequence of the stem analysis, annual stem growth in 1955 was the least. For example, the tree that had grown 3, 300cm³ in 1952 had growth of 203cm³ in 1955. And the stem growth was about 0.3m³/ha in 1955, about 1.1m³/ha in 1956, about 1.2m³/ha in 1957, about 3.0m³/ ha in 1958, about 5.6m³/ha in 1959, about 6.1m³/ha in 1960 and about 11.2m³/ha in 1961.
3. At Yamashina, the stem growth of red pine infested with a great number of Sugi leaf-beetles was about 10% of the normal in 1956. And the height-growth of red pine damaged heavily by these beetles at that time was less than the normal in 1961, but the tree injured lightly had already the normal height-growth in 1960.
Besides, in case of red pine at Higashiyama and Tanabe, the number of pine caterpillar was estimated from the results of this investigation and the feeding quantity of this larva.
For example, it was estimated that the red pine stand at Tanabe had been infested with about 210, 000 pine caterpillars per hectare at damaged time.

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Some part of nutrition contained in the green leaves of trees transfer from leaves to shoots, stem or roots, and the other parts of nutrition remained still in leaves will be returned to soil with fallen leaves in defoliation season.
In this paper, the author reported the results of three experiments on the mineral translocation in this season using 1-1 larch (Larix leopsis) seedling as test trees.
These experiments carried out to solve the following questions; how amount nutrition will be transferred from leaves to other parts of the seedling, and to which parts of the seedling it will be mainly transferred.
1) Table 1 showed that nitrogen, phosphorus and potassium contained in yellowish colour leaves are decrease of about 40_??_70% compared with those in green colour leaves, but calcium is little decrease. It is necessary to take thought for the differences of nutrients concentrations between green leaves and yellowish leaves may be caused by the situation differences of leaves in a shoot as shown in Fig. 1. From these results, however, the author supported that the nitrogen, phosphorus and potassium contained in leaves will transfer from leaves to other parts of seedling about 40_??_70% of the leaves nutrition, and calcium does not almost transfer and be returned to soil just as it is.
2) The author experimented on the changes of the dry-matter content and the nut-rient concentrations in each parts of the seedlings from October to December.
As shown in Fig. 2, nitrogen and phosphorus in green leaves became decrease and those in stem, shoots and roots became increase distinctly in this season. From the results of Fig. 2 and Fig. 3, the author supposed that the nitrogen and phosphorus will transfer from leaves to stem, shoots and roots in defoliation season. Potassium concent-ration in green leaves, however, became increase distinctly in contrast with the nitrogen or phosphorus tendency, and this element in stem, shoots and roots became increase indistinctly in this season. Therefore, the author supposed that the potassium in green leaves will move differently with the nitrogen or phosphorus in green leaves in defoliation season.

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It has been planned by selecting narrow crowned trees to raise planting materials which should give high yield on unit area basis but individually show slower diameter growth, so that the production of quality wood is economically realized. Possible number on an unit area for each tree, that is a theoretical number when only the similar trees are supposed to fill the stand, was calculated by the method of point density estimation (Spurr 1962), and was compared with the crown diameter of that tree. The sample is too small to give a reliable conclusion, but the results show that the tree number is approximately inversely proportional to the square of crown diameter (Fig. 3). However, when the stem size is fixed, increase or decrease of tree number seems to be proportional to 0.66 th power of reduction or augmentation of crown diameters (Fig. 4 and 5).

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In this report, author shows a way to estimate the optimum tension of the multi-span track cable, which is fixed at the both terminals but allowed to run through the each intermediate supports. When a single carriage load is applied on one span selected as the main span, some cable length run into the main span from the unloaded adjacent spans, and the tension increase in the main span is moderated, that is, the tension in loaded cable is regulated by the neighboring spans. In estimating the optimum tension of the main cable, author tries to take the regulation action into account by using the correction-factors of sag-span ratio.

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