Studies were made on the role of food reserves in regrowth during the early stage of regrowth in bahiagrass (variety Pensacola) after defoliation. For this purpose the plants were grown in the growth chamber filled with C^<14>O_2. 1. Food reserves which were stored in stubble and roots decreased rapidly after defoliation and it appeared that a part of decreased food reserves was used for synthesis of new leaves. As a part of previously accumulated food reservescont ained with C^<14>O_2 was found in the new leaves of bahiagrass a few days after defoliation, there- fore it was definitely cleared that food reserves in stubble and roots of the grass were used not only for respiration but for synthesis of new leaves directly. 2. In synthesis of new leaves, food reserves were used for about 6 days after defoliation and there-after they were not used for it in this experiment. 3. Under light condition, new leaves which were synthesized with food reserves made active photosynthesis and the dry weight of new leaves increased from 6th day after defoliation, but under dark condition the dry weight of new leaves did not increased any more. 4. It seemed that the part attributed to reserves in regrowth of bahiagrass was higher in stubble than in roots.

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This paper gives the results of study on effect of light on the utilization of food reserves during the early stage of regrowth in bahiagrass and Italian ryegrass. The following observations seem to be justified under condition of this experiment. 1. In early period after defoliation, the regrowth of new leaves mainly depends on the utilization of food reserves, but later it depends on photosynthesis of new leaves in the grasses. 2. Dark condition during early few days after defoliation was more favorable for development of new leaves than light condition. It may be caused by the difference of utilization of food reserves between light and dark conditions. As one of the reasons of this fact, it seemed that under light condition the respiratory loss of food reserves was higher and the rate of utilization for synthesis of new leaves was lower than under dark condition. But it was not clear under condition of this experiment, and many other experiments are necessary to clear this problem.

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In previous paper, the authors have proved that food reserves were used for synthesis of new leaves during the early stage of regrowth in bahiagrass. In this paper, the authors had some trials to know the process of food reserve utilization for new leaves in bahiagrass (Paspalum notatum FLUGGE) and Italian ryegrass (Lolium multiflorum LAM.) under dark condition. 1. The authors have used following formulas as index to show the utilization efficiency of food reserves in regrowth of the grasses, and the data in_previous papers were used for these formulas. Utilization ratio =Decreased dry weight of stubble and roots during the period of regrowth/Dry weight of stubble and roots at cutting time×100 Regrowth-utilization ratio =Dry weight of new leaves/Decreased dry weight of stubble and roots during the period of regrowth×100 2. In the experiments with bahiagrass, utilization ratio was 40 to 50 per cent, and regrowth-utilization ratio was about 20 per cent a few days after defoliation, and in Italian ryegrass the corresponding numbers were 35 to 40 per cent and about 40 per cent respectively. 3. It seems that those indexes are useful for quantitative measurement of the utilization of food reserves in regrowth of the grasses. In this trial, it has been found that species of grasses and temperature during regrowth had considerable influence on the utilization ratio and regrowth-utilization ratio in bahiagrass and Italian ryegrass. It appears that further studies on this problem are required.

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For the purpose of establishing reasonable soiling system in early sowing of oats in warmer area of Japan, Okayamakuro (early variety) and Onward (late variety) were sown at three different dates (early September, late September and early October) and their growth behaviors and yields were determined. 1. In these three sowings, the cutting time that gained the highest yield was between late April and early May. 2. Regrowth yield was better in the cutting of low shoot apex period. 3. In each sowing, the highest yield was gained by one utting from late April to late May. Whenever cutting number increased, applying cutting time between boat leaf stage and flowering stage was the most important point. Further, the yield of the early variety was not much influenced by two or three cuttings, but the cutting method must be taken with care in severe winter of February. 4. In early sowing, the early variety was better than late variety in yield. 5. In frequent cutting method, following cutting dates were suitable from the growth behavior of oat plant: In case of three cuts for soiling oats sown in early September, 1st cut should be-from late November to early January, 2nd cut-from early March to middle March and 3rd cut-from late April to late May. In case of two cuts, 1st cut be-down to middle January and 2nd cut-from late April to late May. In case of two cuts for oats sown in late September, 1st cut should be-down to late January and 2nd cut-from late April to late May. In case of two cuts for oats sown in early October, 1st cut be-from early March to Middle and 2nd cut-from late April to late May.

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For the purpose of establishing reasonable soiling system in early sowing of Italian ryegrass in warmer area of Japan, it was sown at three different dates (early September, late September and early October) and their growth behaviors and yields were determined. 1. In these three sowings, the cutting time to gain high yield was between late April and early June. 2. If cutting was made in early April in which growth stage advanced, the regrowth yield was expected more 10kg per 3.3m^2, because the regrowth was greater. 3. In each sowing, the maximum yield was gained in one cutting made between boat leaf stage and flowering stage. Whenever cutting number increased, the principle applying cutting time between these two stages was an important point. In total average yield, it was possible to gain more than 20kg per 3.3m^2. 4. In frequent cutting method, following cutting dates were reasonable from the growth behavior of Italian ryegrass: In case of three cuts for soiling Italian ryegrass sown in early September, 1st cut should be-from early December to middle January, 2nd cut-from middle March to late March and 3rd cut-from late April to early June. In case of two cuts, 1st cut be-from early December to middle January and 2nd cut-from late April to late May. In case of three cuts for the grass sown in late September, 1st cut should be-from late December to early February, 2nd cut-from early April to late April and 3rd cut-from early May to early June. In case of two cuts, 1st cut should be-from early March to late March and 2nd cut-from late April to middle May. In case of two cuts for the grass sown in early October, 1st cut should be-from middle February to late March and 2nd cut-from late April to middle June, or otherwise 1st cut-from early March to late March and 2nd cut-from late April and 2nd cut-from late April to late May.

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1) Types or seral stages of grassland vegetation are characterized by two methods: dominant and charcteristic species. Then the judgement of grasslands by the floristic composition is done from such two viewpoints. 2) The dominant is the greatest species in "dominance" in a community at a time. The dominance is expressed by the cover and height ratio as the summed dominance ratio (SDR) and the relative dominance (SDR'), or the multiplied dominance ratio (MDR). They are culculated by the summation or multiplication of the ratios of cover (C') and Height (H'), namely, SDR=(C'+H')/2% and MDR=(C'×H')/100% (Table 1). The constituent species are sometimes treated as superspecies or ecological group of seral equivalents, for example, Lespedeza bicolor superspecies. Japanese main types of mesophytic grassland used for grazing and mowing are Miscanthus-, Zoysia-, Pleioblastus-, Sasa-, Pteridium-, and Poa pratensis types, addition to these, Imperata- and Cynodon types when we consider them including tropical and subtropical grasslands. The establishment and dynamics of a grassland type is shown in Fig. 1 by an example of Miscanthus type grassland. And we can often recognize mixed types of main grassy species as the co-dominants (Table 2). They are pools of pure types or precursory types of grassland and become special, simple types under the biotic pressure. The competitive relation of such pure types is determined by some outer influences, i.e. biotic pressure and climaitc condition. For the ecological judgement of grasslands in detail, the autecology of main grassy species, especially their life history and vitality will be important. 3) The judgement of grassland condition by the characteristic species is connected with the plant indicator. Phytosociological studies on the classification of grassland vegetation are very few. Here some pioneer works and the author's studies are reviewed. The presences of constituent species of Miscanthus type grassland are examined (Table 3). The value of plant indication is restricted in case of local characteristic species. Arborescent species appearing in the course of grassland succession are shown in Table 4. In Japan the course of succession and corresponding species are closely connected with the climatic regions.

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Five times during June 30 to October 18, 1963, investigations were made on action line of the herd and number of grassland utilization regarding to topographical differencies of pasturing area, observing their action all the way with the herd. And from 1960 to 1963, general behavior of pasturing cattle was observed on 496 diary heifers reared by pasturing. The results obtained were as follows: 1) Concerning cattle migration from the action of pasturing animals, definite line of migration was not observed, they having passed all places in the pasturing area more than twice. Moreover pasturing animals mostly went down to valley to drink water in the afternoon in all three seasons and they in all pasturing plots slept almost there in the same places. 2) Numbers of grassland utilization showed a tendency to increase in accordance with the increase of pasturing days of the plot, its main cause being related with its grass-stand. 3) As general behavior of pasturing animals, grazing herds classified by monthly age gradually showed to compose autonomous populations. On the otherhand, though the reasons of escaping off fence were observed to be bad habit, natural damages, desire to drink water, grass-stand in and out of the fence, destroyed fence and others, escaped cattle in all cases showed strong instinct of returning back to the original herd. Grazing herd as well as herd in lying rest hardly migrate and cattle in herd did not make moving much except looking for astray cattle or for drinking water.

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Some digestibility experiments were conducted with sheep in order to determine the seasonal variations in the content of digestible nutrients of Pensacola Bahiagrass and its consumption. Five experiments were tried from early June to early November in both years, 1963 and 1964. The grass was cut at the height of 50〜70cm and stall-fed in every trial. In midsummer trials, the forage consumption decreased considerably, while animal preference was observed rather good presumably in spite of high air-temperature rising up over 30?℃ at its maximum every day (Table 4). Digestibility of all nutrients were very good in almost all trials (Table 5). Seasonal changes of dry matter and digestible nutrients were rather little ranging 21〜33% in dry matter, 13〜18% in TDN, and 1.0〜2.0% in DCP (Table 6). Yield of the grass was sufficiently high during the growing season of early July to early October (Fig. 2). Hence the auther suggests that Pensacola Bahiagrass will be expected to spread because of its high production i.e., about 6,000〜8,000kg green roughage per 10 a per year for several years under good conditions of high temperature, abundant sunshine and adequate fertilizers.

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