Grafting and tree form reshaping method of three-branch inarching of closed apple orchard

The invention relates to technology to transform a closed apple orchard through the combination of grafting and tree form reshaping and discloses a grafting and tree form reshaping method of three-branch inarching of the closed apple orchard. Three-branch grafting is carried out at the root of a fruit tree, three scions are grafted at the subcutaneous section and comprise one long scion and two short scions; after the grafted branch buds, the central tree trunk is formed through three-branch inarching, the height of the tree in the current year can reach up to about 2.5m, and the formed central tree trunk can be pruned according to different requirements of the tree form to be reshaped from the next year, thereby realizing improvement of fruit tree breed and fruit tree form in a short period of time.