| A State-I class protect level on Davidia involucrata and Davidia involucrata var.vilmoriniana (English name=dove tree) includes analyses of the biological characteristics, reproductive phenology ecological characteristics, phenology, community structure, plant diversity characteristics, and natural regeneration. The intent of the study is (a) to provide useful information to help in the in situ protection and conservation of this tree species using only minimal interference and, (b) to determine how to break through breeding difficulties involved with certain ex situ conservation efforts, and (c) to increase the public's knowledge and consciousness of how to protect the dove tree. The preliminary conclusions reached in this study are a result of field research in the Houhe Nature Reserve and the Qizimei Mountain Nature Reserve:The dove-tree community has a vertical, three-tier structure: an arbor layer, an under-story layer, and a herb layer. The dove-tree population is a growth population and the population's age distribution basically in an anti-"J"-type, having a large population of young individuals, a number of medium-aged individuals, and a few big trees. Once the community matures, the number of big trees increases.On the whole, the plant diversity of a dove-tree community is rich with the floras following the pattern: herbaceous layer > shrub layer > arbor layer. Human activities have fragmented the dove tree's natural distribution. At the edges of the dove-tree community the species diversity decreases significantly and the natural regeneration of the dove tree shows a higher mortality rate among its saplings. Asexual reproduction is the main form of regeneration.The effect of location and climate on the dove trees in different parts of the Wuling Mountains affects their reproductive phenology. These location and climate differences make the dove tree sprout, unfold its leaves, flower and produce fruit earlier in the QiZimei Mountain Nature Reserve than in HouHe Nature Reserve.Because the dove-tree seeds involve asexual reproduction, the dove-tree's distribution is plexiform. Usually, one finds several larger trees at the center of a dove-tree site with some smaller trees and saplings surrounding them. Dove-tree seedlings are able to accommodate to a cool environment and light conditions when young but with increasing age the dove-tree seedlings demand increased light.The conclusion from this comparative study of morphological characteristics of Davidia involucrata and Davidia involucrata var. vilmoriniana follow:â‘ a significant difference exists between the under surface of the leaf of the two kinds of Davidia involucrate. The under surface of the Davidia involucrata leaf is covered with yellow or white, short, thick, silk-like, single-celled hairs, whereas the under surface of the Davidia involucrata var. vilmoriniana usually is of light color, but without hair. In a few cases, the under surface may be covered with a dredging of fine"wool"along the leaf veins. The under surface of newly opened leaves commonly are covered with a white powder; andâ‘¡seeds of Davidia involucrata and Davidia involucrata var. vilmoriniana have significantly different external shapes. The seed of Davidia involucrata are much longer and slimmer and have a deeper shell crack. The seeds of Davidia involucrata are about 1 cm longer than those of the Davidia involucrata var. viloriniana, the average seed width is about 0.9 cm wider than that of the Davidia involucrata var. vilmoriniana and seed weight is about 1318g per 1000 numbers more than that for an equivalent number of Davidia involucrata var.vilmoriniana seeds.
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