We have taken up four grasses and legumes (or-chard grass, Kentucky 31 fescue, tall oatgrass, alfalfa, red clover, birdsfoot trefoil and Ladino clover) with a view to examine their adaptability to Sanyo district. For three years (1960-1962), we have investigated the effect of cutting upon yield and its seasonal distribution of pasture plants in pure stand and the following results were obtained: (1) The comparison of 3 years' total yield among them disclosed that Kentucky 31 fescue and Ladino clover yielded highest through any stage of growth at the time of cutting. (2) Increase in the number of cutting (for example, cutting when they were 30 cm in height) caused decrease in yield. This was especially so in perennial ryegrass. As for legumes, its tendency varied with species. Namely, alfalfa and red clover decreased and there was almost no change in Ladino clover. (3) Each of the pasture plants showed a seasonal distribution of yield peculiar to them. The difference in growth stage at the time of cutting scarcely evident in this tendency. Kentucky 31 fescue had the smallest seasonal variation. Orchard grass continued excellent growth from April to the beginning of July and lost growth vigor in summer. This summer depression of growth grew worse with a lapse of year. Tall oatgrass was vigorous in May and June, and it declined slightly in summer season, recovering its growing in fall. Perennial ryegrass grew very vigorously in April and May, but with the rise in temperature it declined, resulting in marked summer depression of growth. The recovery of growth in the fall season could not be expected much. Alfalfa made a small varition of yield distribution. Birdsfoot trefoil showed vigorous growth in the spring season of the first year next to red clover, but with a lapse of year it declined in growth conspicously. As to the variation of distribution, it was smaller next to alfalfa. The growth of Ladino clover in spring season was vigorous but its growth in summer and fall season declined after the second year. Red clover grew very vigorousely from April to July and declined after summer season. It showed a conciderable recovery in the next spring, but its yield decreased year after year. (4) Concering the change of yield with a lapse of year, authors findings were follows: The richest yield of grasses was obtained in the second year it decreased, but recovered in the third year. Among legumes, alfalfa had the highest yield in the second year but other legumes decreased with a lapse of year. Those which showed smaller yield variation among pasture plants were Kentucky 31 fescue and alfal-f a, and those with larger variation were perennialr yegrass and red clover.

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As dead stumps of Oryzacae grasses like orchard-grass are often observed on meadows like converted fields from lowland paddies after first summer of utilization, orchardgrass was sown (seed from Snow Brand Seed Co.) on experimental grassland of Toyama Livestock Experiment Station on September 26, 1963 to check how utilization methos like cutting can reduce summer wilt and elevate grass productivity thereafter. Sowing was made on point at 10×10cm. Cutting methods taken were as follows: 1. Cut at 5cm from ground when grass reached 20cm high (abbreviated as 20-5, same below), 2. " 10cm " " " 20cm (20-10), 3. " 5cm " " " 35cm (35-5), 4. " 10cm " " " 35cm (35-10), 5. " 5cm " " " 50cm (50-5) and 6. " 10cm " " " 50cm (5-10). Six treatments above were replicated three times, one plot each cccupying 2 × 2m=4m^2. 1) Among cutting height taken, low cutting compared with high one always produced slower regrowth after cutting, spending more days for recovery. It also made stems markedly decrease in number in warmer summer season and ultimately produced more withered stumps, thus allowing weeds to, invade the plots with low forage yields. 2) Percentages of withered stumps after summer in respective treatment shown in increasing order were 20-10…20.1 %, 50-10…40.9%, 35-10…52.6%, 50-5…72.8%, 20-5…92.0% and 35-5…98.0%. In treatmnets 20-5 and 35-5, it looked as: if no stumps survied but in 20-10 about 80% survived. And the percentage in none cutting plot as control was 59.0%. 3) The highest forage yield in each plot was shown in treatment 35-10 as air dry weight 1, 906.6g/1. 96m^2 by 6 cuttings. Others shown in decreasing order were treatment 20-10…1, 714.8g with by 14 cuts, 50-10…1, 673. 3 g by 3 cuts, 35-5…1, 647.0g by 4 cuts, 50-5…1, 616.4 by 8 cuts and 50-5…1, 422.1g by 3 cuts respectively. From the results shown above, it may be considerd that in earlier stage of grass regrowth, high cutting and frequent utilization are desirable.

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1. A field experiment was conducted during 1963〜64 to study the effect of irrigation on growth and yield of forage crops on the mineralsoil of the warmer district, compared with prevalent volcanicas hsoil, changing the method and the amount of water application for each irrigation. 2. Effect of irrigation to mixed forages was high in summer season and it was remarkable in Ladino clover which increased length of leaf-stalk and leaf area. The dry matter yields in irrigated plots were 40% more than that in non-irrigated plot. 3. Soil erosion and the running off of the added fertilizeres by the irrigation water of contour ditch method were very slight. So this method seemed to be very useful to the pastures in slope land, though the dry matter yields were 1〜6% less than that in perforated-pipe method. 4. Water requirement changed with season, and it is conjectured that about 3.5〜5mm per day in May to early July and 5.5〜6.5mm per dayin midsummer are adequate amount of water supply fort he grass-legume mixtures in warmer district.

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1) Newly bred N (Nasu)-line No. 4 of Italian ryegrass was sown to upland field from late August through late September of the next year at about half a month interval. 2) Germination was good at average daily temperature 6-23℃, while time to germination period being shorter at 12-26℃. Germination period at 5-20℃ was the day when integrated average daily temperature after germination reached 110-130℃. Germination below 5℃ was much retarded and that above 24℃ was inferior. 3) Inter-nodal growth of the grass was faster in calendaar days in accordance with earliness of germination period. But the days spent for about 1cm growth after germination was longer as earlier the sowing. 4) Total forage yield up to July was higher as earlier the sowing but the sowing from early August to late October gave 1.5-1.8 ton/a. Daily forage yield was higher when the grass was sown at August-October or February-March. 5) The followings were observed that above 5℃ in average daily temperature grass growth incresed, at 10-20℃ vigorous growth attained, at 20-25℃ growth declined as higher the temperature and above 25℃ serious summer depress of growth resulted. From above, it was made clear that production efficiency was highest with vigorous growth in April-June and next to this the efficiency was higher in October-November with good growth. 6) In crude protein content, differencies were not observed regarding to growth stage nor sowing period. 7) Better method of cultivating Italian ryegrass is to get higher forage yield with better production efficiency by effectively utilizing two seasons of optimum growth temperature in spring and autumn. In autumn when average daily temperature goes down below 25℃, it is desirable to sow seed as early as possible.

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1) Germination was tested, using N (Nasu)-line No. 4 of Italian ryegrass, in glass tray, on filter paper and on soil under almost constant temperature. 2) Germination was good even in low temperature as low as about 5℃ whenever longer gemination period of 30-40 days was allowed and it was as good at 5-30℃. But germination was very bad at 35℃, no germination being observed at 40℃. 3) Water abosorbing speed of the seed was faster at higher temperature and time required to water saturation was the time when figures of treated temperature multiplied by figures of treatment duration reached about 1,500. Further, amount of water absorbed to saturation was almost similar to seed weight. 4) Lower limit of gemination was below 2℃. Germination started on 32nd day at 2℃ and on 29th day at 3℃. But when testing time is limited less than 30 days, lower temperature limit will beat 30℃. 5) By studying effect of high temperature treatment (of 35℃ and 40℃ for 5 and 10 days) to germination, under dry conditions, normal germination like control seed was obtained after exposed to 40℃ for 10 days whenever proper moisture and temperature were given thereafter. But by treatment under humid condition, almost no germination was observed with proper management of moisture and temperature after exposed to moist condition at 40℃ for 10 days. 6) Using filter paper as seed bed, covering seed with stagnated well water niether for short time nor full time gave harmful effect to germination. 7) When soil was used as seed bed, of which moisture at 40%, 60% or 80% of maximum water content of the soil, not withstanding either with soil cover to seed nor without, germination was good. But at 30% soil moisture, germination was extremely bad. At 100% soil moisture, however, germination was good when seed was not covered with soil, but with soil cover the higher the temperature the worse the germination.

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Tap root survivals of three legumes, ladino-, redclover and alfalfa were investigated with regard to stand-thin-ning of these legumes which occurs so often in the warm region of this country. These plants were space planted on 16th Sep. 1960 on the field and half the plants was applied severe cutting treatment in 1961, that was six times at the height of 5cm including summer defoliations and the other half was applied four times at 15cm. Five plants were dug at random from the field every two weeks to measure their fresh weight of both top and root. The root diameter at the 5cm from the crown part was measured at the same time. In this experiment, tap root was confined to upper 20cm in length of the root detached laterals. Total available carbohydrate(TAC for short) content of the root was also analysed by WEINMANN'S method once a month. Stand-thinning was markedly observed on red clover in wich the plants almost disappeared from the field by August of 1961 irrespective of cutting treatments. This is closely related with the growth of its tap root as shown in Fig. 2. Tap root also decayed in ladino clover as shown in Fig. 1, this brought, however, its stand-thinning temporarily and thinned stand was recovered by the elongation of newly grown stolons after September 1961, though there observed some lateness in recovery on the severe cut stand. Alfalfa stand kept very well throughout the growing season, none of the stand-thinning being observed. This coincided with the root growth of this species. (Fig. 3) It became clear from the observation of the root that one of the main causes of the root decay was presumably the contraction of diseases in the soil and that some attacks of insect favoured this disease invasion. This process of the root decay is shown in Fig. 4 in which figures indicate the followings: 0. indicates the healthy root, 1. indicates the root which is attacked by the insect only, 2. indicates the root which occurs some necrosis and 3. indicates the root almost decayed. In this Figure, it is clear that the insect attack precedes the disease invasion in both clovers, but not in alfalfa which is more resistant to the diseases, though there observed some insect damages. TAC analysis of the root (Fig. 5) seems to reveal a relationship between this content and the root decay, that is, there are some grounds for susceptibility to the diseases on the side of plants because there odserved the minimum content of TAC before the occurrence of the root decay. From this experiment, it may be concluded that the stand-thinning or life-shortening of some legume pastures is due to the root decay of legumes and that the root decay is caused by soil fungi primarily and some insect attacks favour this fungi bye asing the invasion through their wound.

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In this trial, classification of growth types and relationships between growth types and some characters, such as plant-height, number of stems, green-weight and others is red clover in the second year were studied, by using five varieties, differing their earliness in flowering. The used varieties were Hokkaido local variety, Kenland and Medium red (imported from U.S.A.) as early-, Silo as intermediate-, and Altaswede as late-flowering type. The results were summarized as follows: 1. More flowering type of plants were found in early-, while more non-flowering type of plants in late-flowering variety; and wider distribution of growth types in intermediate-flowering variety. 2. In the investigation of the relationships between classification of the growth types by BIRD (1948) in the first year and that of the growth types in the second year, conformity was not clear in the first crop; while about the half agreed with the growth types in the first year, and the other showed the discrepancy toward the direction of more advanced growth in the second crop, which were similar to the first-year plants in their growing habits. Further studies are needed in this problem. 3. In the investigation of the influence affecting the second-year plant growth in prevention of flowering and seed-setting by cutting the plants in the autumn of the first year, setting up the cutting and the non-cutting treatments, some characters of the first crop in the non-cutting treatment were significantly better than those of the cutting treatment in some varieties and growth types. These results were rather difficult to explain in view of better winter-hardiness in non-flowering plants, and further studies should be needed. 4. The tendency was found that Silo and Altaswede were significantly better in some tested cha racters of the first crop among varieties, and 0 -II types of plants among growth types; and also, about reverse in those of the second crop. 5. Regarding to the differences in some characters within each growth type among varieties, the results were that Silo and Altaswede, which are intermediate and late in flowering, were significantly better in some tested characters of the first crop than the other early-flowering varieties. This showed that there were significant differences in some characters among populations (varieties), even though plants belonged to the same growth types. 6. The investigations were carried out in the first crop of Silo to test the differences in some characters within the same variety among growth types, and the results showed that flowering or III and IV types of plants were rather earlier in flowering than the other growth types, and non-flowering or I and II types of plants were significantly better in the tested characters than the other growth types. This showed that there were significant differences n some tested characters among growth types, eveni though plants belonged to the same populations (varieties). 7. The correlations between plant-height and green-weight, and also, between number of stems and green-weight within each growth type were all in high significance, and their correlation coefficients were almost similar. 8. Node-rooting and subsequent growth of secondary plants were more remarkable in the late-flowering variety and non-flowering type of plants, which were more vigorous in their growths, than in the early-flowering varieties and flowering type of plants. 9. Relationships between growth types and selection for the related characters in redclover breeding, and changes in characteristics of varieties in their seed increases under different environments, and the other related problems should be the important research objects in the near future.

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