Abstract: The damage of the near mature stands of Cunninghamia lanceolata (Chinese Fir) plantations by the frost and snow press disaster was investigated in Dagang Valley forests in Jiangxi Province. The relationships between the harm extent and stands structure, or site index were analyzed. Three main conclusions were drawn. 1) Frost and snow press disaster had caused a proportion of up to 66.84% Chinense Fir plants damaged in Dagang Valley forest. The harm was severe, and the harm of Chinese Fir plant could be divided into six stypes: top bended, top broken, trunk inclined, trunk broken, stem conversed and uprooted, among which, trunk broken and top broken were the major harm types. 2)The stand structure of Chinese Fir had obvious regulation effect on loss caused by the frost and snow press disaster. The relatively small trees were more vulnerable to the disaster than the bigger ones, and the bigger the diameters of trees were, the more gently the harm extent was. The stand density had significant and positive correlation with harm intensity of stands, and the high density stands had more damaged plants. Stand density mainly affected two irreversible harm types that were trunk broken and uprooded. Reasonable density control was very important for resistance of Chinese Fir to the frost and snow press disaster. 3)Site condition of Chinese Fir stands was closely correlated with harm extent, and the stands in high altitude, high slope location and steep slope were more vulnerable to the frost and snow press disaster. The stands with relatively high site index alleviated damages by the frost and snow press disaster.

Key words: Chinese Fir plantation, frost and snow press disaster, harm types, diameter class, density, site condition