Abstract
Penthorum chinense Pursh were transplanted to the artificial planting ground at the waterside of the reservoir. The selective weeding of oppressive herbaceous plants had done for initial 3 years and the sweeping weeding had done in early spring for 5th to 8th year. No management had done since 9th year. The number of P. chinense had decreased since 3th year and had disappeared in the many quadrats since 9th year. On the other hand, The number of P. chinense had increased in the added quadrats where litters were removed early in spring and plants except P. chinense were weeded early in summer. These results suggest that the adequate condition for germination and the removal of competitors in the growth stage are important for perennial appearance of P. chinense. Many seeds of P. chinense were buried in the soil of the planting ground and germinated when the top soil were cultivated. Though seeds of P. chinense were germinated in the water, the seedlings did not grow.
