Abstract: The effects of clipping on production of grassland dry matter in Hong Kong has been studied using different clipping frequency.The results show that:(1)Production of dry matter declined significantly with clipping,and the more frequent the clipping,the more the production dropping.(2)The grasses were more effected than woody plants and other herbs by clipping.(3)Repeated clipping for long term had a severe effect on production of dry matter.Once the net primary productivity of grassland be depressed,it should take a long time to be restored. Low clipping frequency is suggested in order to keep the productivity of dry matter in grassland of southern China.

Key words: clipping, grassland, production of dry matter, effect, Hong Kong