The effects of forest stand formation, forest floor vegetation, crop cultivationon top soil erosion and infiltration capacity of soil were examined in the prospective site for reforestation with fast-growing tree species in degraded forest land and agrof orestry in the Luzon island (Philippines). There was a positive correlation between rainfall and sediment yield. The erosion rate was high for the bare land and the ginger field, while low for the cogon grassland. The reason for the higher erosion rate of the anabiong and kakawate forest over the cogon grassland was attributed to the fact that since the forests were very young, the litter layer and net system were not yet developed while the cogon grass coveredthe ground completely at a high density. The infiltration capacity of each plotis divided into three groups. The infiltration capacity of Group-A was 200mm/hrand below, group-B ranged from 400 to 700mm/ hr, and group-C was 1, 500mm/hr andover. Group-A corresponds to the burned sites. Group-B mainly includes the young (8-12 years old) man-made forests. The characteristics of group-C which were observed in the forest floor exhibited a thickdeposit of litter and organic matter, a well-developed root system and many holes andscats caused by earth worms. The development of the forest environment confirmed that the physical properties of soil showed a transition to a porous structure contributingto the increase ofthe infiltration capacity, and of soil and water conservation.

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To study woods structure of shrine and temple precincts in urban and suburban areas of Okayama City, Okayama Prefecture, relationship between woods structure and properties of shrine and temple precincts (area of open space, owner, dominant landuse around precinct and war damage in 1945) was examined. Factor analysis of variables showing woods structure indicated that woods structure could be explained with three factors showing total biomass, openness, and biomass per area and individual respectively. Total biomass factor scores and openness factor scores depended upon area of open space, and factor of biomass per area and individual depended upon owner. Total biomass factor scores were high but openness factor scores were low in large open spaces. Factor scores of biomass per area and individual were high in shrine precincts and low in temple precincts. Analysis by Hayashi's Quantification Theory III of species composition and precincts showed that tree species often occurred in shrine precincts and subtree or shrub tree species did in temple precincts. These results are useful in quantitative understanding of the woods landscape in shrine and temple precincts.

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