Takiue Pasture of Hida-Osaka Town is located in Gifu Prefecture, in the central part of the main island of Japan. The pasture is divided into four sections, and one of them (the 4th section) being situated at about 1200m above the sea-level and some 50 ha in area, is lately established to be used as a summer grazing pasture for the Japanese black breed of cattle in 1968 (see Fig. 1). Formerly, seedlings of Japanese cypress (Chamaecyparis obtusa) and larch (Larix leptolepis) were planted in this section after the destruction of natural woodland dominated by oak (Quercus mongolica var. grosseserrata) and Japanese cypress with luxuriant understory of dwarf bamboo (Sasa senanensis), but now a pure stand of dwarf bamboos, native plants in this area, so completely covers to hide the tree seedlings. The number of cattle grazed there in 1968 was 76, and the area practically used was less than one third of the section (about 15 ha). On October 22 in the same year, soon after the five months summer grazing, an ecological survey was carried out in this section to investigate the direct effect of summer grazing in the first year upon the vegetation of such a dwarf bamboo type grassland. According to the results of the survey, some matters were clarified as follows : 1) Almost all the vigorous leaves of the dwarf bamboos were lost by cattle grazing, greenish tone of color of the grassland turned to brownish-gray, and the grassland itself seemed to have become quite different in physiognomy. Howerer, few invaders or newly migratory plants were found there, and the scassland scarcely changed in the structure of the community. 2) Not a few tree seedlings were damaged by cattle grazing. Branches were broken by browsing in 15% of Japanese cypress seedlings (1.5-2.0m high), and about 40% of seedlings of larch (1.0-1.5m high) were scratched by trampling at the basal parts of their trunks. 3) The dwarf bamboos in the grazed plots showed a tendency to shorten the height. The higher the culm was, the more it was severely damaged by grazing, and at the end the dwarf bamboos in these plots were more averaged in height with each other than under ungrazed condition (see Fig. 2). 4) Under grazed condition, the dwarf bamboos had many diminutive branches at each node in the upper part of culms over 40cm high above the soil surface, although neither branches near the soil surface nor sprouts from rhizomes were seen. Number of branches per culm were 23.7 in the grazed plots, as against 0.95 in the ungrazed plots (see Tab. 1). 5) The dwarf bamboos in the ungrazed plots had large leaves though comparatively few in number, but the leaves in the grazed plots were very small in shape and abundant. It was ascertained that the average length and the number of leaves in the ungrazed plots were 23.7 cm and 9.2, though 3.6cm and 19.0 respectively in the grazed plots (see Tab. 2). 6) The standing crop (oven dry weight per m^2) of all organs above the ground was measured. It was 1587.3g in the ungrazed plots and 1521.0g in the grazed plots. The dwarf bamboos in the grazed plots were charcteristic in weight that culms (with culm sheaths, branches and leaf sheaths) were heavier and leaves (only leaf blades) were much lighter than those in the ungrazed plots. The weight ratio of leaves to culms was only 1.4% in the former, but was about 30% in the latter (see Tab. 3).

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In 1967 the effects of ammonium sulfate application on the chemical composition and feeding value of Kentucky 31 tall fescue grown in the werm Setouchi district were examined into the form of hay of the first growth and regrowth. A stand of ky 31 tall fescue established in the fall of 1966 was treated with high and low levels of nitrogen application. In the high level plot, nitrogen was applied at a rate of 24kg per 10 a for the first growth and 20kg per 10 a for the regrowth. Within the 4-cut schedule 20kg nitrogen for the regrowth was topdressed with 8kg, 6kg and 6kg after the first, second and third cutting respectively. The amount of nitrogen in the low level plot was a half of the high level plot on each occasion. For the purpose of investigating the response of regrowth forage to the topdressing of nitrogen, a non-nitrogen-topdressing plot was also included in the above-mentioned treatments. The first cutting in each plot was made at the vegetative, boot and head stages respectively in the progress of maturity, and the second to fourth cuttings. at the vegetative stage were obtained repeatedly from the regrowth forage grown after harvesting at the boot stage in the first growth. To determine the digestibility of hays, rabbits were employed to which hays in a powder form was fed. 1) As to the hays of the first growth and regrowth, the contents of crude protein, pure protein and nitrate increased due to the high-level-nitrogen-application whereas the contents of crude fiber, crude lignin, phosphorus, calcium and magnesium did not increase. 2) The contents of DCP in the first growth and regrowth hays increased due to the high-level-nitrogen-application, but the contents of DOM and TDN in the corresponding hays showed almost no change. In the first growth, a declining rate of DCP with the progress of maturity was 0.62% per day for the hays under the high-level-nitrogen-application and 0.18% per day for the hays under the low-level-nitrogen. A declining rate of TDN with advancing maturity was 0.84% per day for the ones treated with the high-level-nitrogen and 0.97% per day for the hays treated with the low-level-nitrogen. 3) There was found an increase of the yields of DCP and TDN per 10 a due to the treatment of high-level-nitrogen-application throughout the first growth and regrowth periods. 4) As to the hays of the second to fourth cuttings, the average contents of crude protein, pure protein, nitrate and DCP as well as the total yields of DCP and TDN under the nitrogen application of both levels increased due to the topdressing of nitrogen when compared with those of non-nitrogen-topdressing. 5) Crude protein (CP) was a prominent component for prediction of DCP content, and crude lignin (CL) for TDN content. Their relationship is explained by the following equations : DCP=-3.37+0.93 CP (S.E.±1.3) r=0.977 (P<0.001) TDN=77.05-3.37 CL (S.E.±7.6) r=0.666 (P<0.01) where DCP, TDN, CP and CL are given in percent as dry matter.

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A field experiment was perfomed to examine effects of root residues of grasses on the growth of following grasses and legumes. Three tropical grasses, two temperate grasses and two legumes were seeded on plots, which were planted by orchardgrass or Italian ryegrass previously, and on fallow plots. In the first cuttings of tropical grasses before mid-August, a little yields were obtained from grass-planted plots than from fallow plots. In the growth of tropical grasses after mid-August and in that of temperate grasses in all seasons, decreases in nitrogen absorption and yield reductions were recognized in grass-planted plots, when insufficient nitrogen fertilizers were applied. In legumes, there were little differences in growth among the plots, except yield decreases of ladino clover in autumn by deseases in grass-planted plots. It is thought that effects of root residues of grasses were due mainly to available-nitrogen deficiency caused by root decomposition.

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To overcome the summer depression of temperate grass yields in southern and central Japan, many researches have been conducted hitherto. The authors tried to examine the adaptability of green panic as a green fodder producer. Green panic, which is now in the stage of introduction into our country, is annual in Japan as a result of winter-killing. In this experiment, the seeds were harvested in 1966, which were sown in June 1967 in our Institute (volcanic ash soil), In this paper, the effects of N, P, K, application are described, and the chemical analyses of the grass harvested are also presented. The findings are as follows. 1) To harvest 200g/m^2 of dry matter yield at each green cutting at 20 days' interval in pre-heading or head-emerging stage, the absorption of 6 and 5g/m^2 of N and K_2O, respectively, is required at each cutting. 2) To harvest 400g/m^2 of dry matter yield at each cutting at 30 days' interval in early heading stage, the absorption of 10 and 7g/m^2 of N and K_2O, respectively, is required at each cutting during the summer season. At final cutting in autumn, however, absorption of 5g/m^2 of each element is estimated necessary. 3) To harvest 550g/m^2 of dry matter yield at each cutting at 60 days' interval in the stage of mid or late heading, 11 and 8.3g/m^2 of N and K_2O, respectively, are required. 4) Because of volcanic ash soil, P rates in this experiment did not affect the grass yield. Green panic produces about 1kg/m^2 from June to September in our locality.

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High moisture silage (84.8% moisture content), 10% wheat bran added silage (78% moisture content) and low moisture silage (60.2% moisture content) were made in three identical tower silos (diameter : 2.64m and height : 4.75m). These silages were tested of organic acids composition, dry matter recovery and digestibilities. And also, milk production and physical conditions were observed of 6 cows for 8 weeks by the Latin square design. 1. The silages were ensiled from Orchard grass and Ladino clover mixture by means of forage harvester in early June 1966 and fed out during the following autumn. 2. Silo 1 was filled with untreated high moisture forage, silo 2 was ensiled by the same material with the addition of 100kg of wheat bran per ton of forage and the material for silo 3 was made wilt before ensiling. 3. In the case of silo 1, 2.21 tons of seepage from 10.5 tons of ensiled forage was recorded and 0.13 tons of seepage from silo 2 which contained 10.7 tons of ensiled mass was observed. No seepage was found from silo 3. Average composition of the seepage from silo 1 was obtained as 1.0316 of specific gravity, 6.47% of dry matter, 4.23 of pH and 0.26% of total nitrogen. 4. pH, organic acids composition and digestibilities of those silages are presented in Table 1. The 10% wheat bran added silage contained high lactic acid and low butyric acid than high moisture silage. But, iow moisture one contained 0.570% of butyric acid on fresh metter basis. 5. Dry matter loss through top spoilage, spoilage during feeding period and gaseous loss by weighing in and weighing out method have been summarized in Table 2. 6. Six Holstein dairy cows were divided into three groups. The silages were fed ad libitum as a sole roughage to each group and the concentrates corresponding to one fourth of 4% FCM were given. Being fed ad libitum cows consumed 11.65kg of dry matter from the high moisture silage per head daily, 13.97kg from the 10% wheat bran added silage and 14.10kg from the low moisture silage. Dry matter intake and body weight gain of cows fed by the low moisture silage were greater than others, but there were no significant differences among the three silages on 4% FCM production. 7. Erythrocyte count and values of heamatocrit, hemoglobin and blood sugar of the three groups were not found over the physiological limits during the experimental period. But, concentration of keton bodies in urine of cows fed by the low moisture silage had a tendency to increase slightly, although the characteristtics of urine were not found abnomal.

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1. In the present paper are given descriptions of the developmental stages of the clover leaf-roller, Olethreutes doubledayana BARRETT, with notes on the discrimination of it from other Tortricid pests of leguminous forage crops in the northern part of Japan. 2. This species has been known to occur in Europe, China, and Honshu, Japan. By the present authors further records of the distribution were taken from Hokkaido and Shikoku, Japan. 3. The larva was found commonly on the white clover, rarely on the red clover, but not on the alfalfa and the sweet clover. The wild host plant has yet unknown in Japan. 4. Light trap records showed that this species may be univoltine at Sapporo, Hokkaido, and bivoltine at Morioka, Honshu. From the results of rearing experiment at constant temperatures, it was also estimated that the insect might be trivoltine at Sendai, Honshu. 5. In Tohoku district the larva is active from mid or late April to early September. The flight period of the adult extends from mid May to late September at Sendai, from early June to late September at Morioka, and from early June to early September at Sapporo, respectively.

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Dry matter production of orchardgrass swards was investigated and some analysis of its growth was made in 1967 and 1968. The effects of two levels of cutting height on growth were compared under two levels of nitrogen fertilizer treatments. This paper deals mainly with the overall response of the sward to the seasons, and the results relating to these treatments will be described in detail in the following papers. Plants were harvested at 5 to 10 days interval for a period of 6 to 10 weeks in early spring, spring, summer and autumn. Leaf area and dry weights of leaf blade, leaf sheath, stem, root and litter were measured. Dry matter yield per year was 720g/m^2. Dry matter yield per day (Y) was the highest in the early spring and the lowest in the autumn. Net production per day (P_n) was the highest in the early spring and the lowest in the summer. The seasonal change of P_n corresponded with that of net assimilation rate (NAR). Y/P_n ratio was 40-50, 71 and 21% in spring, summer and autumn, respectively. It was considered that Y/P_n ratio was of importance in determining the yield. It was indicated that the low yield in summer was associated with the low P_n caused by high temperature, etc., and that the low yield in autumn was associated with the low Y/P_n ratio. Root dry weight decreased more sharply and remained small for longer duration after cutting and recovered slower in summer than in the other seasons. On the contrary, in autumn, root weight did not decrease much and increased again from the early stage after cutting. In autumn, plants had higher C/F ratio than in spring and summer. The growth process after cutting was classified into three stages, 1) the stage in which leaf sheath, stem and root weight decreased, 2) the stage in which leaf sheath and stem weight increased gradually, and 3) the stage in which root weight increased quickly. Leaf area indices (LAI) reached to 5.5 to 6.0 at about 30 days after cutting in spring, summer and autumn, showing not much difference among those seasons. But in summer, 1967, LAI was only 3, presumably leaf growth was inhibited by high temperature and drought. Leaf area duration had high positive correlation with P_n except in summer, when P_n was low in proportion to leaf area duration. The growth was characterized by rapid shoot growth and high P_n in early spring, relatively high P_n in spring, low NAR and P_n in summer, and vigorous root growth and high C/F ratio in autumn.

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A lot of studies on the effects of cutting height have been made in many countries, but no consistent results were obtained. In Japan, HIROSE et al and WATANABE et al reported that higher height of cutting was favorable than lower one, which was reported by REID, HUOKUNA, etc. In the present study effects of cutting height in orchardgrass sward were investigated not only yield (Y) but also on net production (P_n), Y/P_n ratio, dry weight of leaf blade, leaf sheath, stem, and root, leaf area index (LAI), relative leaf growth rate, specific leaf area, net assimilation rate (NAR), crop growth rate (CGR) and relative growth rate. The experimental cutting height were 7cm (close) and 15cm (lax) from ground level. Y per year in lax cutting was lower than that in close cutting by 20%, whereas P_n per year was nearly the same in both plots. The cutting height influenced on both P_n and Y/P_n ratio and the effect of cutting upon P_n and Y/P_n ratio varied by season. In summer, lax cutting had higher P_n and Y/P_n ratio than close cutting. On the contrary, close cutting was superior than lax cutting in autumn in these respects. Both close and lax cutting had merits and demerits for growth characteristics and these relative merits of cutting treatment vary by climate and soil condition, species comprising the sward and system of sward management. The beneficial effects of lax cutting can be summaried as follows, 1) larger leaf area remaining after cutting, 2) heavier root weight and 3) more reserve substances than close cutting. On the other hand, beneficial effects of close cutting were, 1) higher RGR in the early stage of regrowth, 2) higher NAR, 3) higher Y/P_n ratio, and 4) lower C/F ratio than lax cutting. It was concluded that in southern Japan lax cutting was favorable in summer, since high temperature inhibit regrowth after cutting.

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Effects of nitrogen fertilizer application to orchardgrass swards upon dry matter prodction were studied for two years. High (2N)-and Iow (N)-nitrogen plots received 250 and 125kg nitrogen fertilizer per hectare, respectively. Beneficial effects of nitrogen fertilizer appeared both in net production (P_n) and yield/net production ratio (Y/P_n). Mean P_n per day for a year increased from 8.45g/m^2 in N-plot to 11.67g/m^2, or 138% in 2N-plot. Effect of nitrogen fertilizer for P_n varied by season, increasing more in spring and summer than in autumn. Y/P_n ratio increased in 2N-plot compared with N-plot 34, 3, 60 and 6% in spring, summer, autumn and early spring, respectively. Yield (Y), which was indicated as P_n×Y/P_n, increased 71% in 2N-plot. The ratio of Y in 2N-plot to that in N-plot was the lowest in summer among seasons. In 2N-plot dry weight ratio of leaf blade to total plant increased, while that of root to total plant decreased. Consequently, dry weight ratio of non-photosynthetic organs to photosynthetic organs (C/F ratio) decreased in 2N-plot. Relative leaf growth rate of 2N-plot did not differ from that of N-plot in the early stage of regrowth, but the former was higher than the latter from the middle stage to the late stage of regrowth. As a result of such vigorous leaf growth, leaf area indices increased about 2 in spring, summar and autumn in 2N-plot. Net assimilation rate (NAR)-LAI relationship in 2N-plot differed from that of N-plot, and 2N-plot had higher P_n than N-plot at the same LAI level. Crop growth rate increased in 2N-plot markedly, since 2N-plot had both higher NAR and higher LAI than N-plot.

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