Abstract
An ecological study was performed from October 1955 to December 1956 on the natural grassland resulting from cleared pine forest in Hiroshima Prefecture which has a rather warm climate. The land under consideration is a northeast hillside of 15-20°inclination, being formed of granitic gravelly loam with little organic matter. The results obtained are as follows. 1. The vegetation of the natural grassland is composed of 176 species belonging to 59 families, of which 121 species belonging to 37 families are herbs and 55 species belonging to 25 families are shrubs. The natural grassland which developed 3 years after cutting shows richer flora than the grassland which developed 6 years after cutting and the grassland growing under the control pine forest. 2. The vegetational type of the natural grassland may be called "Sasa-Miscanthus and Sasa-Shrub stage" iu the tall grass type, as it is mostly composed of Chamaephytes, Hemicryptophytes and shrubs. 3. The green yield at the newly developed grassland amounts to 800kg per 10 area, of which 60-70% is edible for cattle and which is equal to about three times as much as that at the control pine forest. 4. The grassland developed after 6 years since the cutting of the pines shows the "Second herb stage" with dominating aggressive herbs and inedible shrubs.
