| As an endemic species, Zelkova schneideriana Hand.-Mazz. is valuable for economy and for landscape designing. Because of the over exploitation, the resources become less and less, so that it was listed in Red Dated Book with second grade. The following aspects about this tree, as anatomic structure of leaf and wood, the wound reaction mechanism, the propagation using seeds and cutting, the cultivation and transplanting of more than 20 years old tree, were investigated respectively. Anatomic observation of leaf shown the abaxial epidermis is heteroideous. That means beneath the normal epidermal cells another layer of large cells exists partly, which had well developed vacuole and were less stained. The abaxial epidermis is covered with two kinds of hairs. The short glandaceous hairs are deciduous with maturing of the leaf, while the long pubes was persistent. For the different individuals which have different color in autumn, the morphological features of the hairs may different. The characters above mentioned indicate that this species is somewhat drought tolerant. The stomata distributed mainly in abaxial epidermis. The stomata apparatus consisted of only guard cells which are surrounded by a few un-uniform epidermal cells. Mesophyll tissue is typical heteophyllous, in which crystal clusters could be observed. The ultrastructure of mesophyllous cells, the contents accumulated in these cells shown some differences among the individuals which have different colors in autumn. The wood of this tree is typical ring-porous. The early wood is different from late wood. The formal one possesses large round form compound pores, whereas the later one possesses many spiral vascular tracheid and small vessel elements. The distribution of axial parenchyma cells is also different in early wood from those in late wood. It is paratracheal in early wood, but it is mixed with vascular tracheids and small vessels together forming a wave-like tangential bands. Parenchyma was often full of darkly stained contents or crystals. The content of fiber in sap wood is less than that in hearty wood, which indicate that the rate of different tissues differentiated from cambium varies in different growth periods. Xylem ray belongs to heterogeneous and consists of two kinds of parenchyma cells to form single-or multi-rows. The main parts are made up of procumbent cells. The marginal ray cells are squared cells or upright cells. Vessels of hearty wood have tyloses, which strengthen the character of corrode resistant and guarantee the fine character of wood of Zelkova schneideriana. The tree grows relative quickly in former 30 years, and its annual ring is 3.57mm wide in average. After 30 years, the width of annual ring decreases dramatically. Its mean width is 1.17mm. This result may be closely related to the individual examined tree. After wounding, the parenchyma cells nearby wound secret amorphous slime substances penetrating into the adjacent vessels through pits. Tylosis, functioned as blockage to stop the further diffusion of airs, was also observed in the vessels neighboring wound. These results elucidate that Zelkova schneideriana has a special wound reaction mechanism. The ability of the wound reaction is influenced greatly by the wounding time. In winter, one week after wounding, the parenchyma cells react very weekly. However, in spring, one day after wounding, a large quantity of amorphous slime and phenolic substances could be observed in the tissues nearby wounding. During the process of sexual reproduction, a lot of infertile fruits were produced. The seed setting percentage is only about 5%. The growth rate of seedling from seed shows great difference among the individuals. So it is not proper to afforest with such kind of seedling. Cutting is one of the most effective way to produce seedling with high quality in large quantity. The rooting rate of cutting with 1-3 year old branches is much better than that from adult trees. The treatment with plant growth regulators can promote rooting ability of the cutting. Cutting carrying out in winter using lignified one year branch can result better rooting than in spring. According to variation of leaf color in autumn, four different series of germ plasm can be categorized: (1) the leaf becomes bright red; (2) the leaf turns brown red; (3) the leaf shows pale yellow color; (4) the leaf keeps green till a few days before fallen. For some individuals, the color changing starts in end July or at the beginning of August, whereas others may start in September or October. On the basis of the observation for three years, six types of germ plasm, i.g. JS7, JS8-1, JS8-2, JS9-1, JS9-2 and JS9-3, were preliminarily selected from more than 10 000 seedlings. The selected idioplasm have amazing colors and are suitable for attractive landscape design. Nevertheless, their genetic inheritance is not confirmed, because the population number for selecting is limited. Further intensive and extensive investigation is needed. To promote the survive rate of transplanting adult trees, the key technical measurements are: (1) root cutting is necessary before transplanting; (2) half crown pruning is the most beneficial; (3) transplanting in winter is better than in spring; (4) to take off the new sprouts properly and timely.
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