This article shows the process of map making of urban trees and greenspaces by 1:2000 scale natural colour air photograph and the method to eliminate various errors from the pictures during work. Further more

a series of more than 70000 data about the cover ratio of trees and greenspaces in every 100×100 meter squares within urban area of Beijing were obtained through a density scanner. These figures have been stored in a data base and were used in urban planning

management and urban ecology research.