In the past, in the case of sparse planting of fruit trees, in order to make full use of space, a large number of backbone branches were cultivated, resulting in dense branches and high trees. This not only affects the stereoscopic and high-quality results due to the deterioration of lighting in the crown, but also is inconvenient and labor-intensive.

The current close planting system requires that close-planted trees cannot be closely planted, and high quality and high yield can be achieved through reasonable distribution of branches in the population, so the main branches should be few and small, and there should be more branches. The height of trees should be controlled at about 80% of the row spacing. Dwarf trees are mostly 3 ~ 3.5m, and trees are mostly 3.5m ~ 4.0m, among which the dry height should be controlled at 30 ~ 60cm. The crown diameter shall be controlled within 90% of the height of trees between rows, and the working path shall be ensured above 1 meter. Generally, branches between plants can only be connected, but not connected. Under special circumstances, the connection rate must be controlled within 10%. The forming methods of dental crowns are developing in two directions. One is hedge tree, which is suitable for mechanized pruning and widely used in Europe and America. The second type is flat shed tree, which is suitable for high-quality fruit production and widely used in Japan, New Zealand and other countries.