The impact of understory vegetation structure on growth of Polygonatum cyrtonema in extensively managed Phyllostachys edulis plantation

In order to approach the impact of understory vegetation structure on growth of Polygonatum cyrtonema and establish a theoretical basis for compound management of it in Phyllostachys edulis plantation. The different species composition, physical characteristics and distribution patterns of the understory plants at semi-shady lower slope in extensively managed Phyllostachys edulis plantation were studied. For the research both coorelation and principal analyses to examine diversity indexes of the understory plants with growth indexes of P. cyrtonema were employed. Therefore, to promote P. cyrtonema growing well in Ph. edulis plantation, the abundance of the understory plants should be controlled in-between 159 and 843 ind/m[sup 2] by hilltops weeding in September and October.