The estrogenic activity of alfalfa and ladino clover at different stages of development were estimated by uterine weight responses of overiectomized mice. The results obtained are as follows: 1. The estrogenic activity of alfalfa was low at the bud stage, but it increased remarkably as the plant matured. 2. Throughout the whole growth stage, the estrogenic activity of ladino clover was lower than that of alfalfa and it did not change with the development of growth. 3. Significant differences in estrogenic activity were observed among the three varieties of alfalfa, that is, estimated potency of 100gm. dry matter of Grimm, Du Puits and Rambler at full bloom of the 3rd growth were equivalent to 3.25μg, 1.75μg and trace of diethylstilbestrol (DES), respectively.

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In the grassland ecosystems dominated by Phragmites longivalvis, Reynoutria sachalinensis, and Sasa purpurascens in Obihiro, the production, decomposition, and accumulation of carbon were estimated by the theoretical analysis. The levels of litter, organic matters, organic carbons, and energy per square meter showed high production in the grasslands of P. longivalvis and R. sachalinensis, and low production in that of S. purpurascens. The general equation for the velocity of emission and storation in energy was illustrated by the models for built-up and decay or accumulation in organic matter in grassland ecosystems. In the equations of JENNY et al. (1949), CHANG and RIM (1968), and OLSON, (1963), each has a useful place in estimating decay parameters. For the case of steadystate grasslands, the ratio of annual litter production "L" to the amount accumulation on the top of mineral soil (F, H, and Ao horizon) provided estimates of decay constant K. Estimates ranged 0.376±0.0490 in the Phragmites grasslands, 0.461±0.0359 in the Reynoutria grasslands and 0.146±0.0066 in the Sasa grasslands. The periods required for decomposition of half of their steadystate levels in the Phragmites-, Reynoutria- and Sasa grasslands were 1.842, 1.503 and 4.737 years, while it took 7.978, 6.509 and 20.506 years to loss 95% of the initial levels of the organic carbons. For a "climax" composition, the grasslands need a period of about 3/K years before accumulations have attained 95% of their steady-state levelf.

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1. This report gives the results of Studies on the variation of nutritive values due to the decomposition of some natural litter. Furthermore, the report deals with the theoretical analyses for the variation of the quantity of chemical components. 2. The models used in the theoretical analyses are established as shown in the equations (2), (7), (8) and (9). The analyses were restricted to those components of the litter believed to be of importance. 3. The percentage of total nitrogen per organic matter was negatively correlated with the amount of the decaying litter (organic matter of grasses). However, the C/N ratios in the L, F, H and Ao herizons were positively correlated with the amount of organic matter. 4. The crude protein in the litter was very slowly decayed in the grassland ecosystem, the N-free extract was slowly destroyed, and the crude fiber and fat were decayed with a high velocity (see Figs.3, 4 and 5). 5. The points available for theoretical analyses are the increase of protein and the decrease of fiber due to the decomposition of the litter. 6. Some problems relating to the prediction of digestibility remain to be the increase or decrease of chemical components of litter, but if the decomposition is cut at any optimum point, this principle is applied to the increment of nutritive value.

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For the purpose of knowing the effects of the presence or non-presence of leaves of the basal part of plants after cutting at different heights on the regrowth, trials were conducted in the following design. Plants of Dallis grass were grown in 1/5000 a plastic pots. About 8 weeks after sowing, they were cut at three different heights, i.e. 1, 5, and 10cm above ground level. Each of the three lots were divided into two. 1) In the first lot, the basal part of the plants rimaining after cutting were left with leaves intact, while 2) in the second lot, the leaves were completely removed. In each treatment, replications were made 4 times. And the effects of the presence or non-presence of the basal leaves on the regrowth were studied: ^<14>CO_2 was fed to plant immediately after, 2 days, 5 days and 11 days after defoliation, using ^<14>CO_2 assimilation chamber under the condition of artificial light of 40 klux, 25-30℃, ^<14>C4μCi/each plant. One day after ^<14>CO_2 treatment, the plant of both lots were harvested, making a series of dates of harvest 1 day, 3 days, 6 days and 12 days after the dates of difoliation. The harvested plants were separated into stubble, root and the part of regrowth ; and dry weight, TAC content, and radioactivity of each component were measured. In another series, plants were harvested, dipped in boiling water for a few seconds, dried, mounted and then their radioautographs were made. The major results and interpretation were as follows: 1) In all the pairs of lots, regrowth was faster in those with the leaves left on the stubble than those defoliated, the effect of undefoliated leaves of basal parts being apparently favourable. 2) Increment of dry weight of newly grown leaves was the fastest in the lot of combination of highest cutting height and undefoliation of basal leaves, showing the sharpest upward curve ; whereas it was the poorest in the lot of combination of lowest cutting height and defoliation of basal leaves. 3) Reduction of dry weight of stubble and root after cutting was the smallest, its duration being shortest, and the recovery started earliest and rose most rapidly in the lot of combination of highest cutting height and undefoliation of basal leaves ; while the reduction was heavy, lasting longer and the recovery started slower in the lot of lower cutting height and defoliation of basal leaves. Basal leaves apparently acted to keep the reduction smaller at each level of cutting. 4) Translocation of ^<14>C-assmilates to roots after defoliation started earlier in the plants cut at high levels and in the plants which had undefoliated basal leaves than in the plants cut at low levels and whose basal leaves were thoroughly removed.

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In Japan, simple and effective methods are urgently needed not only to improve glasslands with steep slopes, characteristic to her extensive mountainous areas, but to renovate improved grasslands for maintaining their productivity which tends to decrease within a few years after establishment mainly due to unfavorable climatic conditions. The dissemination of pasture plants by using livestocks was suggested to answer this need because authors sometimes observed clover seedlings on the surface of livestock feces in some pastures, and also because of some results of experiments already reported. The present studies were undertaken with these background. In this first report, the results of experiments were presented on the recovery and viability of the seeds of ladino clover (LC), sub clover (SC), orchardgrass (OG), and Italian ryegrass (IRG) passed through the digestive tract of goat. One gram seeds of each four species enclosed separately in a silk bag were soaked in goat rumen through a fistula on May 24, 1966. After soaking for 8, 24, 48, and 72 hours, the seeds were washed, and classified into two groups, normal and destroyed seeds. Normal seeds were tested of their germination under room temperature. Ten gram seeds of each species were mixed with 400g of concentrate feed and fed to each one of two goats which were placed in separate digestion apparatus on June 20. The goats consumed thoroughly the mixture. Feces were collected and weighed 12, 24, 48, 72, 96, and 120 hours after feeding, respectively. Seeds recovered in feces were counted in 50g feces sampled from each collection, and then tested of their germination under room temperature. Fifty dung-pellets sampled from each collection were pressed on the sterilized soil in each pot whose area was 1/5, 000a, with two replications. Number of seedlings from the seeds recovered was recorded for the period from late June to early November. One more germination test was carried out early September to clarify the effect of goat-body temperature on the germination of seeds passing through the digestive tract. The seeds laid on moist paper in peri-dishes were incubated under 38℃ for 0, 12, 24, 48, 72, and 96 hours, respectively, and then tested of their germination under room temperature. By the retention in goat rumen, the grass seeds were little affected in outward appearance. The clover seeds, in contrast, became destroyed except hard seeds as the time elapsed, as was shown in Fig.1 and Tables 1 and 2. This means that seeds were physiologically affected by soaking in rumen even though they were undestroyed in appearance. Most of ungerminated seeds might become impermeable, dormant, or quiescent. Number of seeds fed to goat and that recovered in feces were given in Table 3. First recovery was observed in the feces defecated for 6-12 hours after feeding in clovers, and for 12-24 hours in grasses. Maximum recevery occurred in the feces defecated for 24-48 hours after feeding. Although the date of last recovery differed a little among species, almost all seeds were recovered within 96 hours after feeding. Total recovery was highest in ladino clover (28%), lowest in orhardgrass (0.6%), and intermediated in sub clover (8%) and Italian ryegrass (7%). Such general trends were similar to the results reported by BURTON and ANDREWS, and by SUCKLING, though they merely determined first recovery on the first day after feeding. Here occurs a question why grass seeds were highly digested by passage through the digestive tract while they were little digested by soacking in rumen. Probably grass seeds were more strongly affected by browsing, etc. in digestion than clover seeds mainly due to the structural difference of seeds cover, glum vs. seed-coat. Average percentage of germination of seeds recovered was highest in Italian ryegrass (36%), followed by orchardgrass (31%), and sub clover (15%), and lowest percentage was obtained in ladino c

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This study was planned to examine how the rate of seeding effect the competition in ladino clover (LC) and red clover (RC) var. Hamidori, mixtures during the vegetative phase. Dry weight, leaf area and length of petiole were investigated and the authors tried to find out the factors, process and intensity of competition. It was carried out from April to July in 1968 and the material was seeded as dense as 3600 plants/m^2 in the large seed boxes. The rates of seeding adopted were LC pure (L100), LC75%・RC25% (L75・R25), LC50%・RC50% (L50・R50), LC25%・RC75% (L25・R75) and RC pure (R100), respectively, and results were as follows. 1) As for the ratio of dry weight in comparison with pure stands, LC presented 47-87% and RC was 31-88%, respectively, in L75・R25. So both species did not suppress each other. On the botanical composition in community, LC occupied 40-66% and kept the balance of the growth, so this rate of seeding indicated the heighest yield of dry matter in all the sowing rates of this experiment. On the other hand, LC gradually decreased to 40-10% and conversely RC increased to 63-102%, respectively, in L50・R50. The botanical composition of LC ranged from 33% to 10%. It was clearly shown that LC was suppressed by the more vigorous growth of RC. The suppressive tendency of RC to LC was more pronounced in L25・R75. 2) Leaf area of RC was larger than LC except 9 weeks after emergence in pure stands. The ratio of each leaf area of two species in mixtures to each pure stands and the ratio of two species in the total leaf area showed almost the same values as dry weight. There were close correlation between leaf area and dry weight. 3) In pure stands, petioles of RC were longer till 9 weeks, but those of LC were rather longer after that time. In mixtures, the dominant species in communities have longer petioles and the difference of the length of petioles became larger in process of time. 4) The ratio of leaf weight of two species in communities in upper 10cm stratum was almost balancing in L75・R25, but in L50・R50 and L25・R75 where RC was usually dominant RC occupied 85-100%. It was presumed that there were much difference of light reception between both species. 5) One of the factors which induced struggle for mastery was seemed the differences of seed size of both species. The weight of 1000 seeds of LC was 560mg and RC was 1550mg. The proportion of LC to RC was approximately one third. There was not suppression, but rather cooperation between both species in L75・R25 where the growth increment of both species since emergence apporoximately equaled by the reason that total seed weight of each species was almost equal. On the other hand, total seed weight of LC was extremely lighter than RC in L50・R50 and L25・R75. It was noticed that there were large differences of the growth increment since emergence between both species and RC gradually became dominant in communities. 6) From the above mentioned facts, it would be concluded that the rate of seeding played an important role in the arrangement also in of the photosynthetic organs and the growth increment during early stage of each species caused by the differences of seed size (weight) and, as the results, varied the degree of their competition.

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Indole-3-glycolic acid was identified as a metabolite of L-tryptophan (Try) degradation by Rhizobium meliloti. This product seems to be formed from indole-3-pyruvic acid, which is an intermediate of Try metabolism, but not from indole-3-acetic acid.

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