2. Shaping and pruning: the crown of Luan tree is nearly spherical and the tree shape is regular, generally using natural tree shape. Due to different uses, its plastic requirements are also different. Roadside saplings require a straight trunk, the height of the first branch is 2.5 meters to 3.5 meters, the crown is complete and plump, and the branches are evenly distributed. Courtyard shade trees require a large and dense crown, and the height of primary branches is lower than that of street trees. In the process of cultivation, corresponding pruning measures should be taken around the above requirements. Generally, it can be done in winter or during transplantation.
3. Planting: Koelreuteria paniculata is a greening tree species, and the planting spacing of urban streets is generally 5_8 meters. As a road center isolation belt, the planting spacing can be appropriately reduced. As street trees, the planting distance of highway greening is generally 5- 10 m, and evergreen trees such as Ligustrum lucidum and Tabai can also be planted, with good results. Most of the Luan trees are mainly Huangshan Luan trees. Because of its weak cold resistance, planting in spring should be given priority to in the north, and cold protection measures should be taken in autumn. Planting in the south can be carried out in spring and autumn. It is best to plant large seedlings with soil balls, and large seedlings above DBH 3cm can be planted with fixed poles according to the actual situation. It is best to apply preservatives to the incision to reduce water evaporation. When planting, the roots should be stretched and watered in time after planting to ensure the survival of trees. Luan tree grows rapidly, and can be pruned appropriately according to the situation after defoliation every year to maintain a good tree shape.