Decomposition of the root of Italian ryegrass under both conditions of the paddy field and the upland field was studied. Naturally the production of CO_2 as a characteristic of organic matter decomposition is more active under the upland condition than the paddy field, and by the application of CaCO_3 than that of three elements (NPK) of fertilizer. Consistency of the soil profiles where Italian ryegrass was cultivated is not so strong as those of other plots where the rice straw and the green ryegrass were added or of the manureless plot. Content of humus and exchangeable bases is higher in the plot of Italian ryegrass than in other plots. The nature and properties of soils where Italian ryegrass was grown became very favorable physically and chemically.

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A fertilization trial in the second year growth of several perennial grass and legume spocies was conducted to analyze the forage yields of the pure stand of the species, namely, timothy, orchardgrass, Ladino clover and red clover. The results obtained are as follows; 1. To ensure a high yield, top dressing must be done at the most effective stage specific to each species: for timothy and red clover in early spring, and for orchardgrass and Ladino clover, after each cutting. 2. The optimum amount of fertilizer to be placed should be determined according to the characteristics of each species; the upper limits are, for clovers lower and for grasses higher. 3. The growth forms responded to the fertilization were different with each species; the yield of orchardgrass and Ladino clover was increased by the dense growth of the lower strata, while that of timothy and red clover was inereased by the top growth, which formed an erect type. 4. The percentage of leaf portion to the total weight was decreased in accordance with the increased fertiilizer at the first and second cuttings owing to the relative increase of non-assimilative parts. 5. The fact that such species as timothy and red clover decreased in their yeild at the second cutting, especially in the highly fertilized plots, was due to the poor regrowth in the lower strata of the productive structure of the grasses. 6. The main yield-promoting factors of the forages were stem length in timothy, the increase of leaf number and the growth of leaf parts in orchard-grass, the increase of the leaf number and enlargement of leaflets and petioles in Ladimo clover, and stem growth in ned clover.

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This experiment was performed to get a fundamental knowledge of the speed of leaf emergence in response to seasonal difference in orchard grass. (1) It was found that orchard grass differed from paddy rice on the system of foliar emergence. In paddy rice, the new leaf blade emerges from leaf sheath of the preceding leaf after its leaf blade has fully developed and elongated. However, in the case of orchard grass, new leaf blade emerged when the preceding leaf had reached 6/10 of its full length. (2) It was made clear that the interval of leaf emergence was shortened in late spring and early summer in orchard grass. However, the growth was decreased and delayed remarkably in mid-summer, (socalled the summer depression of pasture crops), the interval of leaf emergence was prolonged in this period and recovered during late summer to early autumn. These changes in the leaf emergence were closely related to that of the seasonal growth and yield of orchard grass.

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I) Vegetation on each side is as follows. (a) Ecological variation by the distance from the estuary was little recognized at both sides. (b) Imperata cylindrica has the highest dominance ratio, and Equisetum ramosissimum, Artemisia japonica, Arundinera hirta, Sporobolus elongatus, Lespedeza cuneata, and Phragmites japonica, are in due order. (c) Grass types on both sides are Imperata type (60-70%), weed grass type (25-35%) and other grass type (5%). (d) Imperata grows at all grasslands and the grassland may be induced into Imperata type in general, if main weed grasses are cut over. Imperata has the highest frequency ratio, and Equisetum, Arundinera, Sporobolus, Artemisia, Killinga brevifolia, var. leiolepis, Lespedeza and Erigeron canadensis are in due order. (e) PH of soil of the inside grassland is lower than that of the outside. (f) Number of grass species on the inside grassland, is more than on the outside grassland. (g) Phramites japonica and Equisetum grow prosperously on the inside grassland, and Artemisia on the outside. II) Grass yield on each side is as follows. (a) As the meadow, the outside glassland is superior to the inside grassland. From the standard grass yield of Japan, this grassland may be ranked in middle class. (b) It is common defect in natural grassland that yield of Leguminosae is scanty. (c) Main inedidle grass species on both sides are Phragmites japonica, Artemisia, Erigeron, Equisetum, and Themeda japonica. (d) Poisonous grass species is not found on both sides. (e) Grass species that grow commonly at all plots, are Imperata, Arundinera, Sporobolus and Artemisia. Yield of Imperata is the highest, and Equisetu, Artemisia, Arundinera, Sporobolus are in due order. III) Amount of leaves in arborescent Leguminosae is as follows. Lespedeza bicolor is the first in amount of leaves, Lespedeza cuneata the second, and Indigofera pseudotinctoria the third. Lespedeza cuneata is the first in percentage of leaves, Lespedeza bicolar and Indigofera are in due order.

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[in Japanese]

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