1) In this paper, the authors discussed about the relationships between the characters of stubble and the regrowth of herbage plants on the strength of the data of experiments formerly conducted. 2) There was high correlation between the amount of nitrogen in the stubble at the time of defoliation and the tiller number, regrowth-tiller number and the regrowth of herbage plants. 3) There was close relation between the amount of TAC content in the stubble at the time of defoliation and the regrowth of herbage plants, too. 4) It was assumed from these facts that abundant reserve substances and existence of the original tissue of regrowth (tiller, regrowth-tiller) were needed for the excellent regrowth of herbage plants. 5) Therefore, to expect the excellent growth after defoliation, the appropriate managements in herbage culture must be conducted considering these facts.

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1) This paper gives the discussion about the utilization efficiency of reserve substances and the regrowth potential of herbage plants. 2) "Rate of Regrowth=Dry weight of top/Dry weight of stubble and root at the time of defoliation", which was formerly proposed by the authors, was one of the proper index to indicate the regrowth potential of herbage plants. 3) But, it could not indicate the utilization efficiency of reserve substances in regrowing process after defoliation. Therefore, it was proposed to divide "Rate of Regrowth" into "Utilization Rate=Decreased dry weight of stubble and root during the period of regrowth/Dry weight of stubble and root at the time of defoliation" and "Regrowth-Utilization Rate=Dry weight of new top/Decreased dry weight of stubble and root durig the period of regrowth". 4) And it was found that the difference of regrowth potential ("rate of regrowth") among several species of grasses was mainly due to the difference of "regrowth-utilization rate". 5) Therefore, the authors will discuss about the factors which affect the " regrowth-utilization rate" in the next report.

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1) In this paper the authors discussed about the factors which affect the utilization efficiency ("regrowth-utilization rate") of reserve substances in some grasses. 2) The optimum temperature range of the "regrowth-utilization rate" in cool season grasses differed from that in warm season grasses. 3) In cool season grasses, high "regrowth-utilization rate" were obtained under 15-20℃ temperature, and under 25-30℃ in warm season grasses. 4) There was no direct relation between the contents of carbohydrate or nitrogen in stubble and the "regrowth-utilization rate" in all grasses. 5) Tiller number or regrowth-tiller number were the main factors which affect the fluctuation of "regrowth-utilization rate" in the grasses.

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The distribution of the carbohydrates in a plant and its seasonal change as influenced by burning, was studied by dyeing with I-KI solution and chemical analysis of Miscanthus sinensis. In general, the plant consumed reserves in rhizomes for the rapid growth of shoot in spring, and the newer the rhizome, the earlier was the consumption. When the internode began to elongate, the carbohydrate concentration both in culms and rhizomes reached the minimum. Culms accumulated starch mainly at their middle to basal parts, reaching the maximum soon after earing. Thereafter the carbohydrates of culms moved rapidly to rhizomes. After July, the rhizomes began to restore the carbohydrates, and the older the rhizome, the earlier was the accumulation. By burning, the carbohydrates in rhizomes were rapidly exhausted for regrowth and the restoring process was delayed as compared with that of the unburned plant. This trend was more remarkable when the burning was done later. However, even in the plant burnt latest at the end of June, the carbohydrate concentration both in culms and rhizomes attained the same level as that in the unburned plant by the end of autumn in the same year.

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In this paper, the observation on the influence of the burning upon the culm-number of Miscanthus sinensis is reported. Burning was carried out five times, April 14 (B-414), May 4 (B-504), May 23 (B-523), June 15 (B-615) and June 30 (B-630) in 1967. 1. In the B-504, B-523, B-615 and B-630 plots, 10, 17, 56 and 72% of culms were decayed respectively as the result of direct influence of burning. 2. In the plot B-414, where culms decayed by burning were scarcely observed, the rate of increase in the culm-number soon after burning was low as compared with that in the unburned plot, but became similar to that in the unburned plot later in July. 3. In the B-504, B-523 and B-615 plots, the rate of increase of culms after burning was considerably high, and the culm-number became greater than that in the unburned plot from early summer to autumn. 4. In the B-630 plot, where the time of burning almost coincided with the time when the reserve substance in rhizomes fell to the minimum, the culm-number was 7% less than that in the unburned plot even in late autumn. 5. The withered culms were found so many in those which tillered from early spring to June. The culms withered by some causes during the growth period of Miscanthus sinensis were counted as about 20% in the unburned plot, but they increased in the burning plots, where a higher score as 50% was sometimes recorded. 6. About 90% of culms tillered in July or later overwintered safely. About 5-10% of culms tillered in May passed winter, a part of which survived until autumn. However, no culm which passed the first winter ever survived to pass the second winter.

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A study was made on the effect of burning on the growth of culms above ground as well as branching behaviour of rhizomes of Miscanthus sinensis. 1. In each plot, the mean number of primary tillers from each overwintering culm was about 1.6-1.8. 2. In the U plot (unburned plot), the number of primary tillers which tillered from culms emerged from May to July was small. However, in the burned plots, the primary tillers from culms emerged from May to July increased considerably in number. 3. Even in the burned plots, the number of primary tillers from overwintering culms was almost the same as that of the U plot, but the tillering was hastened. 4. In the plots burned at a later date, the sprouting of secondary or tertiary tillers was accelerated since the emerging of primary tillers was hastened, and the entire number of tillers increased considerably. 5. In the U plot, the number of secondary tillers was about 1/3 of the total tiller number, and the tertiary tillers were found to be small in number. In the plots burned after late May, the number of secondary tillers amounted to about 46-47%, and the tertiary tillers, about 12-17%. Moreover, about 1% of quarternary tillers sprouted. 6. In the U plot, the elongation of tillers which sprouted in the same year was restricted. However, in the burned plots, the culms grew conspicuously in the same year of tillering, and this tendency was more remarkable in the plot burned at a later time.

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Tryptophan (Try) metabolism of Rhizobium meliloti was examined. Indole-3-aldehyde (IAld) was identified as a metabolic product. Indole-3-acetonitrile (IAN), indole-3-acetamide (IAm) and tryptophol (T-ol) were not detected. IAld was not oxidized to indole-3-carboxylic acid (ICA). IAld was not considered to play a significant role in the regulation of Try destruction by this bacterium.

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The effect of clipping on the yield, stand persistency and feeding value of Pensacola bahiagrass was studied in 1966 and 1967. The grass was harvested repeatedly when they grew to an average plant height of 15cm and 30cm, respectively. The results obtained were summarized as follows : 1. No significant differences in the mean contents of DCP and TDN of each clipping were found between the 15cm and 30cm treatments, while the cumulative yields of DCP and TDN were much higher in the 30cm treatment than in the 15cm treatment. 2. There was almost no difference in apparent deteriorating effects of frequent clipping on the persistency of grass stand between the two clipping treatment.

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Some informations on expression of growth type and flowering of some red clover varieties, investigated in Sapporo, Hokkaido (43°00' N. Lat.), and in Tomobe, Ibaragi Prefecture (36°22' N. Lat.), were summarized as follows : 1. Expression of growth type of red clover varieties was almost similar in cases of March 15-May 15 seeding in Sapporo. This showed that induction of florigenic stimulus was affected by critical day-length, not by accumulated one. 2. Medium type of red clover varieties in June 1-15 seeding in Sapporo was intermediate in their stem elongation, showing wide distribution as 0-IV Types in their growth type expression; while, in July 15 seeding, stem elongation was hardly observed. This suggested that there must have been an essential and effective stand age of red clover plant for induction of florigenic stimulus, responding to daylength. 3. Mean flowering date of red clover varieties tested in Tomobe was 15-20 days earlier in April 15 seeding; while, 30-40 days earlier in June 1 seeding, in which the expression of their growth type was almost similar in both Tomobe and Sapporo, than that in Sapporo. From the mean flowering date and the daylength in both places, the stand age of red clover plant above mentioned was supposed to be about 60 days after seeding in Sapporo; while, about 45 day after seeding in Tomobe. 4. For seed increase of red clover varieties, it is desirable to consider the daylength and the stand age of red clover plant for induction of the florigenic stimulus in corresponding places, in order to avoid a shift of characteristics in red clover varieties. For example, in case of varieties tested, which are adaptable in northern areas, seed increasing place should be chosen in a more northern area from the location of fifteen hours in the longest possible duration of sunshine (about 40°00' N. Lat.), and also, seeding should be done at date of 60 days or more before the latest date of fifteen hours in the possible duration of sunshine. This should be also considered in identification on characteristics of red clover varieties. 5. Growth type seems to be more reasonable as a marker character than flowering, for the identification on characteristics of red clover plant population, especially for that in diverse latitudes.

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Oats (Avena sativa L.), orchardgrass (Dactylis glomerata L.), and Rhodesgrass (Chloris gayana Kunth) were growth in the field under 3 levels of population densities, defoliated at several stages of development, and harvested 3 weeks later. It was found in each of the grasses that the changes in dry weight of regrowth with the development of stage showed no differences by population densities, and every grass showed its own specific pattern of regrowth with the development of stage. It was supposed that these patterns of regrowth may be resulted from both environmental conditions, and morphological and physiological conditions of grasses with the development of stage.

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