This study was examined to check the effect of third cutting time in autumn on shoot development and foliage growth in the pure and previously established galega (Galega orientalis Lam.) sward in the following spring. The third cutting time was so critical that the decline in sprout vigor and number of sprouted shoots in the next spring led to the delay in the flowering time at the first harvest, and the decrease in plant length and dry matter yield of the whole 3 harvests in the next year, when the third cutting was hastened to the middle and/or late September from the normal October-cutting. In addition, since the mutual correlation of plant length and/or dry matter yield across each cutting was highly significant, it was considered that the effect of the third cutting time on the aboveground foliage growth continued throughout the whole growing season in the next year. As the emergence of new shoot was restricted to the post-melting snow season with no productive shoot emerged thereafter, the new shoot sprouted from the underground on the stubble in spring should become a main shoot, which was consisting of the first harvest yield. After the first cutting, regrowth and dry matter accumulation could be accomplished by the growing of branches derived from one or several axillary buds existing on the stubble of main shoot, and this regrowth pattern could be repeatable throughout the growing season. Therefore, it was suggested that the shoot growth, contributed to dry matter production at each cutting, should be based on the same underground organ as a supplier of nutrition and water, and thus, the mutual significant correlation in plant length and dry matter yield across each harvest be mediated with the examined developmental characteristics of shoots in galega.

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To identify a target weed in the establishment of Zoysia japonica Steud. on a new levee, we evaluated total and Z. japonica coverage, vegetation height, and species composition. In May 2005, we planted Z. japonica cultivar 'Asagake' at a rate of 25 stolons per m^2 using 10cm long stolons on bare ground. Planted and unplanted plots were mowed to a height of 10cm three times per year (May, July and October) for 2 years. In comparisons, total plant coverage was higher in planted plots in May 2006 and 2007, and vegetation height was lower in planted plots in October 2006. In 2005, Digitaria ciliaris (Retz.) Koeler accounted for approximately half of all plant dominance on both plot types. In 2006, D. ciliaris decreased considerably in planted plots but remained unchanged in unplanted plots. Negative correlations were observed between the D. ciliaris multiplied dominance ratio in 2005 and Z. japonica coverage in planted plots in October 2006 and after, suggesting that D. ciliaris should be a target weed in order to improve Z. japonica growth.

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Rumen fermentation of Japanese Black breeding cattle that grazed on Zoysia japonica Steud. -dominant pasture was compared with that of cattle that grazed on a temperate grass (Dactylic glomerata L. and Festuca arundinacea Schreb.) -dominant pasture in spring, summer and autumn. In spring, the total VFA and ammonia-N in rumen fluid were higher in cattle that grazed at the Zoysia pasture than in those that grazed at the temperate pasture. In summer and autumn, the difference was decreased. The difference in rumen fermentation between the pastures was not significant, but the difference among seasons and interactions of pastures×seasons were significant (P<0.01). These results were partially caused by the greater than 30% of the legume dry matter composition at the Zoysia pasture in spring, which led to lower NDF and higher total N contents at the Zoysia pasture. In contrast, the proportion of legume decreased in summer and autumn. These findings suggested that the digestible energy and crude protein contents of plants ingested by the cattle grazing in the Zoysia pasture was as high as those ingested by the cattle grazing at the temperate grass pasture.

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We studied the vegetation, dry matter production and consumption of the established pastures for gathering cattle, which were composed of temperate pasture plants, in a vast forest grazing land. The coverage of the pasture plants was higher in the pastures established by using compost pellets and macro seed-pellets than in the pasture that established by sowing. The rate of herbage production was the maximum from spring to early summer; it reduced in midsummer, and recovered in autumn. Although the annual dry matter production was >800g/m^2 in the first year, it was reduced by almost 50% in the third year. The proportion of herbage consumption to the herbage mass varied yearly with the seasons; the variation was almost within the range of 40-80%. The annual herbage consumption rate, defined as the proportion of annual herbage consumption to annual herbage production, was high at 0.71-0.90 during the 3-year period of the study.

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The chemical composition of spikelet-decreased strains (M645 and Ouushi403) and the common variety (Bekogonomi) of forage paddy rice (Oriza sativa L.) stored as round-baled silage was compared, and the difference in the digestibility of these silage by cows was examined. In addition, the influence of the field loss of grains due to the wilting process in the case of M645 was examined. The panicle weight ratio (dry matter basis) of M645, Ouushi403, and Bekogonomi silage were 28%, 47%, and 53%, respectively. The starch contents (dry matter basis) of these silages were 10%, 17%, and 22%, respectively. No significant difference in the total digestible nutrients (TDN) content was observed among these silages (54-55% of dry matter). On the other hand, the digestibility of organic cell wall of M645 (53%) was higher than that of Bekogonomi (44%). In the case of M645, the TDN content was not influenced by the wilting process which decreased the panicle weight ratio to 17%.

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Techniques for plant classification and identification are not only used to identify the taxonomy of species but also serve as important tools in criminal investigations. However, morphological and DNA analysis are very difficult when only trace amounts of plant materials are available. Thus, it is necessary to develop a technique for classification and identification of plant species based on biological and chemical substances from diverse and small amount of sample. Therefore this study was conducted for classification and identification of plant species by comparing pattern of peaks using pyrolysis-gas chromatography (Py-GC), which reflected the species-specific lignin structure of the cell wall. One mg of dried samples from each of 26 different Gramineae species was pyrolized, and we obtained species-specific pyrograms that were not related with sample size and structure. Cluster analysis based on selected 30 peaks showed that 26 different Gramineae species could be classified into five major groups: Cluster I, Cluster II, Cluster III, Cluster IV and Cluster V. Cluster I group consisted of 3 species namely Cynodon dactylon (L.) pers., Pennisetum purpureum Schumach, Brachiaria decumbens Stapf. Cluster II group consisted of 15 species that were under genus Zoysia and Oryza sativa L. ClusterIII group consisted of 6 species that were 3 species of genus Paspalum. Cluster IV and V consisted of Cenchrus ciliaris L. and Agrostis stlonifela L., respectively. We used modified BLAST (wwwBLAST ver. 2.2.17 from NCBI) analysis of amino acid sequence program for identification of plant species. Out of 26 different Gramineae species, six plant species were collected from different sites. Among these 6 species, four species were identified successfully using this system.

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An artificial forest of Japanese larch (Larix kaempferi) was strong-thinned into four stem density stands. Each stand was divided into a disturbed litter-layer plot and a control plot. We then sowed seeds from six pasture plants into both plots. After three months, all pasture plant species had established better in the disturbed litter-layer plots than in the control plots. In addition, fewer Aralia elata and Rubus crataegifolius were found in the disturbed litter layer plots than in the control plots. Therefore, we conclude that litter-layer disturbance had positive effects on the establishment of pasture plants.

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