Abstract: Different cutting experiments were executed on well-grown natural Imperata cylindrica vegetation in red soil region.The biomass of every 6 years cutting was the highest,and the annual cut was the lowest.Annual cutting resulted in the highest total accumulative biomass in 6 years,with a total production of 399.1kg per plot.The species composition was also influenced by the length of cutting period.In the 6th year of experiment,the xylophyta biomass in the treatment of every 6 years cutting accounted for 41.5% of the total biomass,while the herb biomass in the treatment of annual cutting was 99.0% of the total.The length of cutting period also influenced the layer's development of soil profile and the physicochemical properties of soil.In comparing with the treatment of annual cutting, the soil bulk density in the treatment of every 6 years cutting was lower,and the contents of soil organic matter,total nitrogen,available phosphorus and available potassium were higher.

Key words: Red soil, Natural vegetation, Cutting period, regeneration type, micro-topographic unit, reproduction mode, ecological species group., relict plant