In the first experiment, Pensacola Bahiagrass (Paspalum notatum FLUGGE) was grown in nutrient solution, and effect of deficient culture of each macrountrient (N, P and K) in the solution on regrowth of the grass was determined. Each of the three macronutrients was deficient in the solution during the 8 days before defoliation, the first 8 days and the secoond 8 days following defoliation respectively. Among the macronutient deficient groups, as the result of the experiment it was found that effect of nitrogen deficiency in the nutrient solution on the regrowth of Bahiagrass was most significant and that of potassium was slightly recognized, however there was no difference in the regrowth behavior between the plants grown in the phosphorus deficient nutrient solution and those grown in the standard nutrient one. Among the nitrogen deficient groups, the nitrogen deficiency during the 8 days before defoliation was most remarkable on the regrowth of the grass, and air dry weight of new top and number of tillers decreased significantly in this solution. It appeard that this effect was moderate in the nutrient solution which nitrogen was deficient during the first 8 days following defoliation and was least in the solution which nitrogen was deficient during the second 8 days following defoliation. Among the potssium deficient groups, air dry weight of new top of Bahiagrass was lowest in the solution which this nutrient was deficient during the 8 days following defoliation, and it decreased scarcely in the solution which potassium was deficient during the 8 days before defoliation. In the second experiment, Bahiagrass was grown in the pot with soil under the 20℃ and 33℃ temperature glass chambers in phytotron, and all plants were defoliated on August 18. Top dressing of bitrogen was ed to the pots at different times according to the following schedule: Series A, no treatment, series B, nitrogen on August 10 (day-8), series C, nitrogen on August 18 (day 0) and series D, nitrogen on August 26 (day+8). In the 20℃ temperature condition, air dry weight of new top of the grass was highest in the plants grown in series B (day-8), and that of the plants grown in series D (day+8) was lowest among the treatment plots. Similar tendency was observed for stubble and root. In the 33℃ temperature condition, air dry weight of new top of the grass was highest in the plants grown in series C (day O), and it was lowest in the plants grown in series D (day+8) among the treatment plots. The first experiment was carried out in about the same temperature as the 20℃ temperature chamber in the second experiment, therefore it was considered that the results of the nitrogen deficient period investigation in the first experiment supported the results obtained in the 20℃ temperature condition in the second experiment.

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A study was made to clarify the effect of thick planting together with its yield increasing function and lignification of main stem by checking relationship between planting distance and optimum cutting time as well as forage yield using Kurosengoku variety of soiling soy bean. 1. Significance of between-row distances was very high, that of cutting times fairly high and that of between-hill distance no more than slighly recognizable. Namely, the narrower the between-row distance, the higher the yield, and the combination of 18cm between-row and 6.5cm between-hill made forage yield very high in 30-60 days after sowing. 2. Main reason of increased yield by thick planting was due to increased number of plants grown per unit area. But in different planting distances under equal planting density, the cultivation of narrow row distance and wide hill distance of 18 cm×6cm (i. e. 108cm^2) gave better growth and higher yield than that of 36cm×3cm (equally 108cm^2). Concerning planting distances, though there was slight significance in between-hill distances, to make between-hill distance not too narrow seemed to be one important yield increasing factor whenever between-row distance would be narrow. 3. The plants grown by thick cultivation showed lower leaf blade- weight ratio (green leaf blade weigt ×100/ green body weight) and high day matter weight ratio (dry matter weight ×100/ green body weight after 40 days since it was sown. 4. Lignification of main stem was observed up to the 3rd node in 50 days after sowing and up to the 7th node in 60 days. In these parts, degree of lignification was observed to be between 5 and 3, their water contents were low and dairy cattle fed such lignified soy bean left some amount uneaten

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1. Though hay making can be mechanized by using large type machineries, one deposit of finished hay cnsists of seven to nine processes of works and they make frequent visits of machineries to grassland. Consequently the soil there is tightly packed, the solidity down to 15cm below ground surface becomes higher, solid phase portion of the soil increases and porosity rate decreases. 2. Soil packing be farm machine tread on mixed sown pasture grasses brings poorer regrowth of grasses after cutting and it results in lower forage yield. Particularly when cut grass is left on the field for sun drying, number of withered plants increases, speed of regrowth retards and consequenly the lowest forage yield results in. 3. A series of experiments were conducted concerning soil packing by farm machine tread, height of cutting and effect of cut grass left on the field. The results obtained were as follows: a. Growing speed of regrowing leaves was highest in plots of on treat and as number of tread increased, growing speed slackend, the slowest regrowth being shown in plots of 5 time machine tramplings. Treatments by various cutting heights and by cut grass handlings showed no clear differences. b. Green forage yield showed exceeding differences by tread treatments. One time tread gave the highest yield, and 0, 3 and 5 time treads gave respective lower yields in that order, the last one i. e. 5 time treads giving the lowest yield. c. Number of surviving plants were few in plots of frequent tramplings like 5 and 3 treads and occurence of withered plants was observed there. Many number of plants survived in the plots where trampling number was few like 0 and 1. In plots where days cut grass left on the field were many or where cutting height was low, number of surviving plants was few, and in plots where cut grass was carried out of the field at once or where high cutting was made, surviving plants were many in number. d. The results of cut grass handling and cutting height after top-dressing ammonium sulphate and 3 time machine tramplings showed that number of withered plants increased and green forage yield was lowest when cut grass left 7 days on the field and grass cut low.

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An investigation was made in the action of a herd consisting of 35 Holstein and its hybrid hyifers during pasturing from May through October, 1960. The results obtained were as follows: 1) Four forms of herd's action were observed, vid. grazing, resting, mixed type of above two and migrating. Each of these action forms showed different seasonal distribution. Total time of herd's action was longest in June and it decreased as daytime became shorter. But time for grazing form among total action time was shortest in September when grass production was low and longest in June with its high grass production. On the contrary, the times for mixed and resting forms showed reverse tendency and the time for migrating form was marked in June and September. 2) Concerning intra- day changes of each action form, two peaks were observed, one in morning and another in afternoon, in June and when grass production was high, but since Agust restng time was shorter. Rising time of animal for action in morning and resting time lying at night seemed to be connected with the time of sunrise and sunset. 3) Daily forage intake per head of the investigated head estimated by cutting method showed highest at 79.7kg in June and lowest at 27.6kg in August. Daily increase of body weight per head was highest at 0.75kg in May-June and lowest at 0.17kg in August. 4) Results of individual investigation of a heifer picked up from the investigated herd showed time for grazing per day took 8 h 19min, for resting 50min respectively. Distance walked for action in one day was 2,036 meters, numbers of water drinking and salt licking were 0-1 time, and amount of salt taken per day was 33 gr. And number of dung excretion was 2-5 times and that of urination 2-10 times respecttively, particularly urination seemed being connected with climate.

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To ascertain the presence of seasonal types of animal action in pasturing herd, an investigation was made concerning herd's action and topographic and climatic conditions. The results obtained were as follows: 1) Time of herd's action was connected with length of daytime, i. e. longest in spring and became shorter in summer and autumn accordingly, the difference between that in spring and autumn being 2 h. 2) Concerning seasona change of action forms, a tendency was ovserved that mixed form frequently appeared in spring, resting form in summer and grazing form in autumn. 3) In relationship between topography and herd's action, grazing form was observed all over the pasturing area, but in cooler morning and evening it tended to be seen on hillside slope and in warmer daytime on hilltop or in valley bottom. Resting form was taken through all three seasons moreoften on airy hilltop in daytime and on wind protected hillside at night. Actions were mostly observed, therefore, on hilltop in spring and Summer, and on flat area and hillside in autumn. 4) As to the actions in fine day and rainy day among relationships between climte and head's action, grazing time was shorter in rainy days and the reverse was resting time. Moreover time of standing rest was twice longer in rainy day than that in fine day. Time of lying rest contrariwise shorter. 5) In action forms in fine day, grazing, resting and mixed forms alternated but after rain started in rainy days grazing form increaed with decresing mixed form. In rainy day as herd moved to leeward area, bedding time was delayed.

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1. To attain an amazing high production of Italian ryegrass in winter cultivation on lowland paddy of warmer area, effects of irrigation and heavy application of fertilizers were testes in two winter cultivation seasons of 1960 and 1963 at experimental field of Shikoku Station. 2. The result of the effect of time of irrigation and fertilization showed that the longer the irrigation time, the more grass height growth promoted as well as internodal growth, and this tendency was particularly evident in heavy application plots of fertilizers. Yield promoting effcts on green forage and dry matter were various depending on the amount of fertilizer applied, spring irrigation plots giving better yield than full time irrigation plots under the condition of heavy fertilizer application. 3. In comparing three spring time irrigation treatments, namely full time irrigation, intermittent irrigation and no irrigation on the fields of different nitrogen application stages, it was found that though green forage yield and crude protein content showed remarkable increases by heavier application of nitrogen from the end of th previous year through March, there were no yield differences by nitrogen application during the spring time irrigation period. But in total yield, the highest yields were given in the plots of intermittent irrigation plus heavy nitrogen application strongly affected by high production in the spring.

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Two orchardgrass swards of different density were established in the fall of 1963; HD sward, broadcasted at the rate of 2.2kg/10a, 445 plants per m^2 remained alive when snow melted in the next spring, and LD sward, drilled in rows of 37.5cm apart with 15cm distance between hills, about 20 plants per m^2. From April to July in 1964, the development of orchardgrass was divided into six stages (I-VI). At each stage, plant and canopy height, plant weight, production structure including LAI and relative light intensity, CO_2 concentration of the air under canopy and chemical constituents of the plant parts were measured. The results obtained are summarized as follows: 1. The growth of plant in terms of dry matter and tiller number was very poor in the HD sward as compared to that in the LD sward under severe competition for light and other growth factors. However, dry matter production per area was always greater in the HD sward. 2. The Leaf Area Index of the HD sward reached 12 at booting stage and remained almost constant for a while till full head stage and then declined rapidly to 5 due to lodging and death of lower leaves. LAI of LD sward reached to 5.3 even at full head stage. The lower leaves near ground surface of the LD sward always received light contributing something to the dry matter production. However, those of the HD sward could not receive light beyond compensation point at boot stage, and thereafter most of the lower leaves which distributed 30cm above ground surface were under the similar shading. The CO_2 concentration of the air around these leaves reached to 1.5mg/L even on clear windless days suggesting some minus, photosynthesis there. Consequently, the lower leaves, weaker tillers and often whole individuals died resulting in the decrease of density. In the LD sward, on the contrary, no death of plant occurred although with the death of lower leaves to lesser extent. 3. The fructosan content in the stubble was consistently higher than in the rest parts. Green leaves and stems contained always less than 1%, although with higher percentage in green leaf-blade during winter under snow cover. At the end of the previous year the stubble stored more than 25% fructosan, but much of it was consumed under the snow-drift. In the early April, the fructosan in the stubble dropped to 0.2% in the HD and 1.5% in the LD swards respectively, due to consumption for the rapid elongation of plants. Therefore this period may be highly critical for orchardgrass management, especially in high density sward. Thereafter from boot to early head stage, fructosan again increased in both swards, but much earlier in LD sward. Total sugar declined in the both period of spring rapid elongation and of summer maturation with heavier decrease in HD sward in the early April. 4. Green leaf-blade contained the highest amount of protein-N, followed by leaf-sheath and stem and then by stubble. Even in stubble, however, protein-N reached around 3% just after snow melted with higher level in the LD sward. Levels of protein-N in green leaf and stem reached to a peak when stem elongation began, being 5% in leaf-blade and 4% in leaf-sheath and stem and thereafter declined gradually to maturity. The LD sward always contained higher level of protein-N than the HD sward. Soluble-N content showed similar seasonal pattern as proteinN, but fluctuated to lesser degree although with higher content in the stubble under snow cover. It attracted our attention that nitrate-N content increased up to more than 0.3% at the end of April, declining gradually to early head stage and dropped to less than 0.1% thereafter. 5. Most tillers of LD sward which had been formed by December headed in the next spring (11 heads per plant), but the most younger tillers formed later in spring (a part of the primary and most of the secondary tillers) continued vegetative growth. In case of HD sward, on the contrary, each plant ha

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Field plot experiments were conducted in 1964 to find out the factors that affect the yearly change of density in the orchardgrass sward. Two swards of different density (HD and LD) were the same as described in the previous report (II), and one more sward (LS) was added (high density, equal to HD in seeding rate, but band-seeded) to compare its dry matter yield with that of HD plot. The growth stages of orchardgrass plant were divided into the following six stages, at each of which the initial harvest was taken with two cutting heights, leaving 5cm (L) versus 10cm (H) of stubble. I: Early Reproductive II: Boot III: Early Head IV: Full Head V: Full Bloom VI: Mature At each successive cut following the initial harvest plants were clipped when they grew up to 50cm in height. The results obtained are summarized as follows: 1. Density decreased markedly in HD sward, but with no dead plant in LD sward. Death in HD sward resulted mainly from the following three reasons: (1) Death due to mutual shading: Death of weaker plants under shading by stronger plants at the early to full bloom stages. (2) Death due to harvest: a. Death of weaker plants with no recover after harvest from April to early May when the stored carbohydrates in the stubble became minimum resulted from being consumed for the rapid growth of plant under comfortable environment, although much nitrogen was retained in the stubble. b. Death of weaker plants after cutting in July and August-"summer depression"-with a long spell of hot and dry weather near ground surface, although the stubble contained rather much carbohydrates. 2. Generally, plants died less severely when the initial harvests were made at earlier growth stages and at higher level of cutting. However, the difference of the number of alive plants among plots initially harvested at different stages became lesser through the year due to various factors concerned. 3. In the high density sward, dry matter yield of the initial harvest increased with increased growth stage till full bloom, but decreased at mature stage due to lodging of the sward. In the low density sward, however, no lodging occurred and dry matter of the initial harvest was highest at mature stage. Yield and vigor of regrowth for the successive cuts following the initial harvest was more excellent with earlier initial cut, but the total yearly fresh and dry matter yield was highest for the plots initially harvested at full bloom stage, sincethe yield difference among the initial harvests wasso great as to dominate the total yearly yield. 4. Crude protein yield of the initial harvests run almost parallel to that of dry matter. The total yearly yield of protein, however, showed no significant difference among plots of different stages of initial harvest with closer defoliation, but when cutted at higher level showed discrepancy with that of dry matter and increased with earlier initial harvest. 5. Although full bloom stage might be the best to harvest when taking dry matter yield, chemical composition and water content in consideration so far as the forages of the initial harvest be utilized primarily for hay or silage, but the earlier initial harvest might be better from the view-point of protein yield, palatability and persistency of sward density, provided the forages be utilized form soiling or grazing. 6. In case of HD sward, when the intial cut was taken at stage I, the main-stem died by the 2nd cut even if its shoot apex was not removed although few primary branches grew up to heading. When cutted at II or III stage, all main-stem died with their shoot apexes removed and some of the primary branches continued their vegetative growth although some which had already turned into reproductive phase stopped their development of young head due to injury from the cut just above the apexes. In case of LD sward, on the contrary, most main-stem and primary branches were not removed thei

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Some researchers insist that for measuring Palatability of herbage plants, it is practical and sufficient to classify preference standard in 3 or 4 grades. However, it is necessary to measure palatability quantitatively, when we want to determine the degree of palatability in relation to various factors of plants such as their chemical components, digestibility and so on. In Japan, measurement of palatability has been, even in research works, carried out in very questionable ways owing to the deficiency of knowledge about "palatability" itself. Therefore the authors began these studies and first they took up its measuring methods. An outline of the results of the experimental project to compare several methods of measuring palatability of fed plants, their hays and silages were as follows: 1) Tree methods of measuring palatability, (i) eating speed, (ii) free choice between two materials and (iii) free choice among all materials (cafeteria method) were compared with each other. The results of the last two methods were similar and clearly showed difference among materials for both hay and silage. And the first method showed the least difference. 2) Because of this, it is presumable that method (i) would be the most suitable for comparing materials whicn are quite different from each other, but on the contray, methods (ii) and (iii) display much more suitability in case of materials similar in nature. 3) Regarding method (ii), however, testing practices become increasingly troublesome as number of materials increases. So it can be said that method (iii) would be the best way, for it is suitable in every case, simple in technique and prectical. 4) Measurement of eating-ruminating time ratio (E/R) by observing ingestive behavior was tried as one of the methods determining palatability absolutely or in percentage. This method, owing to the difficulty of distinguishing rummaging time for tasty part of the herbage from true eating time, could not be recommended. And it can be said that the method of determining total intake per day or ruminating time per unit amount of herbage intake would be more suitable. Moreover, measuring ruminating speed is one of the most simple and practical methods.

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1) Three methods of measuring palatability of herbage plants, i) by amount of herbage intake, ii) by time of herbage intake and iii) by number of animals attracted, were compared with each other, using 10 steers under the three treatments replicated twice with 8 combinations of 4 grasses and 2 growing stages. 2) Because of high correlation among the three methods, it was presumed that they could be adopted with similar reliability. From theoreticl view point, the herbage intake method has been recognized as the best one. But actually its measuring procedure is comparatively troublesome and liabl to sampling errors. Therefore in short time measurment of 1 hour or less like these experiments, the grazing time method or animal number method would be recommended. 3) In order to check the effect of herd behaviour on selective forage intake, it was compared with individual behaviour by tethered grazing method. Because of the similar tendencies of both behaviours, it was presumed that they would be inter-changeble in measuring palatability. The high correlation between both measuring methods of grazing time and herbage intake was also confirmed by tethering.

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Purpose of these studies were to establish a method by which the highest yield would be secured as well as well balanced high production throghout a year would be expected. On October 12, 1961, orchard grass, Ladino clover, red clover and Italian ryegrass were sown (reseeding being made in autumns of the following years) under treatments of irrigation, water table, amount of fertilizer applied and cutting height to test their effect on yield and botanical composition for tow years. The results obtained were as follows: (1) In Kanto area where dry condition continues in early spring, irrigation was effective in that season, particularly to Italian ryegrass. But in the summer when water table went up high (average 32cm), the favorable effect of irrigation disappeared. (2) Moreover when water table came up too high (average 22cm), orchardgrass and red clover faded away damaged by high humidity, and single vegetation of Ladino clover appeared thereafter was due to this fact. (3) High producing effect by heavy fertilizer application was observed only when Italian ryegrass occupied main part of the botanical composition. But since summer, withered plants produced naked spots in the field and weeds invaded to those spots. Instead of heavy fertilization plots, forage yield was higher in standard fertilization plots (total amount of annual top-dressing being N:P_2O_5: K_2O=2: 2: 5kg/a) and effect of heavy fertilization was not observed in total annual forage yield. (4) By low cutting (5cm), Italian ryegrass and Ladino clover gave higher yield but in orchardgrass and red clover, high cutting (10 and 15cm) gave higher yield. As to total annual forage yield, lower cutting produced high yield but low cutting also induced monopolization of Ladino clover, bringing reduced production in summer and autumn seasons. (5) When water table was low, though low yield in summer and autumn seasons could be somehow controled by standard fertilization instead of heavy one and by high cutting instead of low one, their range of control was very narrow, the total annual green forage yield being about 1,000kg/a.

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