Abstract
To investigate growing roots after tree transplantation, sap flow with the heat ratio method were conducted on two tree species for two years. In case of Magnolia grandiflora L., the highest rate of sap flow was recorded in late July. The seasonal curve of sap flow shows good root development and success of transplantation. In case of Acer palmatum Thunb., two trunks were measured with root balls. One tree had a drainage improved system, while the other was transplanted to bad drainage conditions. Sap flow in the former tree increased favorably and the root system was developed well. However sap flow in the latter tree did not increase and had the sign of poor growth.