This paper is concerned with the determination of carbohydrates in forage plants. Carbohydrates in orchard grass and red clover were for convenience fractionated into four groups according to solubility in 80% alcohol (Fraction-I), 0.25% oxalic acid (F-II), 4.6 N perchloric acid (F-III) and 0.7 N hydorochloric acid (F-IV), and then some properties of carbohydrates in four fractions (F-I〜F-IV) were characterized chemically and physiologically. The results obtained may be summarized as follows: (1) The majority of the available carbohydrate were distributed among F-I and F-II in orchard grass and among F-I, F-II and F-III in red clover. (2) Carbohydrates in F-II of orchard grass were contained much in the stubble and consisted mainly of fructosan as the reserve substance which responded most sharply to the fractuation of the external environmental conditions. In red clover, starch replaced fructosan as the reserve carbohydrates, being much both among F-II and F-III. (3) It was conceivable that hemicelluloses of cell wall constituents were destributed among F-III and F-IV in orchard grass and red clover, because of formation of xylose by hydrolysis in hot mineral acid. (4) From the results described above, the suitable conditions of the extraction with solvents and of the acid hedrolysis of two different carbohydrates in grass and legume forage plants were comparatively investigated. (5) The small amounts of starch were contained in the leaf of orchard grass. In the base of leaf sheath, starch granules by the iodine color reaction were recognized microscopically around the vascular bundle.

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Topdressing and oversowing pasture was first attempted in the spring of 1957 but it did not succeed owing to weeding failure. Three years later, the writers attempted again to convert this abandoned pasture into good one by cutting and fertilization and succeeded this time. The process in pasture establishment and the effect of fertilization was clarified. Effect could be recognized in each of nitrogen, phosphorus and potassium fertilization. The reasons why phosphorus was most effective and potassium not so effective were discussed.

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The present work is the result of research to measure the influence of food reserves and temperature on the regrowth of Italian ryegrass and orchardgrass. Low food reserves were attained by placing the pots in the dark for 4 or 8 days. A preliminary experiment with orchardgass was made under field conditions. A second experiment was carried out in the 15℃, 20℃ and 30℃ chambers in a phytotron. Carbohydrate reserves are important for regrowth of grass. However, term "food reserves" used throughout this paper will refer to the dry weight of the Stubble and roots of the grasses. In orchardgrass, the dry weight of new tops decreased with the decreased of food reserves under field conditions. The decrease in dry weight of stubble and roots stops and the weight increases earlier in the plants with higher food reserves, than in the plants with lower food reserves. There are no great differences between the higher and lower food reserves in the length of time required for recovery. In Italian ryegrass, the dry weight of new tops increased with increase of food reserves in all temperature pots. This tendency was more marked under the higher temperature condition than under the lower temperature. The dry weight of stubble and roots returned to the original level after 16 days of regrowth in the 15℃ temperature treatment. Dry weight under 20℃ temperature started to re cover but did not regain the original level. In the 30℃ treatment, dry weight decreased for the entire period. In orchardgrass, the plants with higher food reserves produced more dry matter in new tops than those with lower foor reserves in the phytotron experiments. However, this tendency was more marked with Italian ryegrass than ochardgrass, The dry weight of stubble and roots of each pot recovered to the original level after 30 days of regrowth in the 15℃ chamber. Dry weight in the 20℃ chamber started to recover after 15 days of regrowth, whereas that of the 30℃ chamber decreased continuously with the exception of the plants with the highest food reserves. In this series of experiments, the rate of regrowth is given as Dry weight of new tops/Original food reserves×100. The increased rate of food reserves (dry weight of Stubble and roots) is given as Food reserves at sampling time-Original food reserves/Original food reserves×100. With Italian ryegrass in the phytotron, the plants whth higher food reserves showed a higher rate of regrowth than those with lower reserves. This tendency was more pronounced at higher temperatures, whereas with orchardgrass there were no significant differences with the exception of the 30℃ chamber. With Italian ryegrass in the 15℃ chamber, the increased rate of accumulation of food reserves was higher in the plants with high food reserves than those with low reserves. There were no significant differences in the rate between plants with different food reserve levels in the 20℃ and 30℃ chambers. In orchardgrass, the increased rate of food reserves was higher in the plants with high food reserves than in the plants with low reserves in the early period of regrowth in the 15℃ and 20℃ chambers. This relation was reversed after 20 and 10 days in the two chambers respectively. These relationships of increased rate of food reserves between high food reserves and low ones were opposite in the 30℃ and 20℃ chambers.

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The present work is the result of research to measure the influence of food reserves, plant nutrients and temperature on the regrowth of Bahiagrass and orchardgrass in the dark. The term "food reserves" used throughout this paper will refer to the dry weight of the stubble and roots of the grasses. In Bahiagrass, light and plant nutrients had little effect on top regrowth for several days after defoliation. Light and plant nutrients influenced top regrowth after 4 and 8 days, respectively. The effect of light on top regrowth was greater than that of plant nutrients. The effect of light on the dry weight of stubble and roots was observed from the start of regrowth. The decrease of food reserves was markedly higher under dark conditions than under light conditions. This showed that the effects of photosynthesis took place earlier on the stubble and roots of Bahiagrass than on the tops. The regrowth of Bahiagrass was better with large than small seedlings in the 15℃ and 25℃ chambers in the phytotron. In Bahiagrass under the 15℃ and 25℃ chambers, the effect of temperature on the speed of regrowth was more pronounced than the effect of food reserves for the early stage of regrowth. The speed of regrowth was higher under the 25℃ chamber than under the 15℃ chamber regardless of the amount of food reserves. However, the dry weight of new tops was higher in the plants with higher food reserves than in the plants with lower food reserves. The same tendency was observed in the rate of regrowth in Bahiagrass. In the plants of orchardgrass with higher food reserves, the dry weight of new tops at the early stage of regrowth was higher under the 25℃ chamber than under the 15℃ chamber. In the case of plants with lower food reserves, the speed and dry weight of top regrowth were higher under the 15℃ chamber than under the 25℃ chamber. The same tendency was observed in the rate of regrowth in orchardgrass. In both grasses, the decreased weight of food reserves was more pronounced in the plants with higher food reserves and under the higher temperature conditions than in the plants with lower food reserves and under the lower temperature conditions.

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Owing to lodging, adjustment of utilization period is not easy in high yield cultivation of soiling winter oats. Considering this fact, some number of tests were conducted to stabilize utilization period of the crop by controling the lodging. In variety comparison test, high yielding varieties were shown to be apt naturally to lodge and a lodging stable varity found was "Zenshin (Onward)". When the lodging was neglected as soiling oats, variety "Hoyo" might be most suitable one because of its softness of leaves and stems and of its high productivity. Mixed cultivation of lodging resistant variety and nonresistant high yielding variety showed favorable result. Mixed sowing of 0.3kg/a each of "Zenshin" and "Hoyo" gave higher yield as well as the lowest lodging rate. In the above mentioned varietal combination, as the distance between plants should be even, it might be desirable to sow seeds twice on the same row.

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