Flat stubble is also plastic pruning:

Cluster trees usually keep 3-4 basic branches extending evenly around as main branches. For 1 year-old seedlings, it should be cut again, leaving only about 20 cm to promote the development of basic branches. 2-year-old seedlings should be planted with 3-4 strong branches as main branches in different directions. The main branches should be moderately shortened, and the trunk should be cut off at about 1/2, and the other basic branches should be cut off from the base. In the third year, the extension branches of the selected main side branches will continue to shorten, forming a happy crown. Branches in the inner chamber are generally not pruned, and attention should be paid to removing sprouted branches in time.