Cultural tree preference and its influence on tree biodiversity in urban public spaces in Nanjing city, China

•Cultural tree is defined as a tree species with important cultural value in tree culture.•Cultural trees were preferred to noncultural trees for both native and introduced species in the designed landscapes of Nanjing, China.•There was an inconsistency between ‘national’ trees in the sense of culture and native trees in terms of their natural distributions.•In Nanjing city, of the cultural species, 54.29% were introduced; of the native tree species, 75.00% had no important cultural value.•The preference for cultural trees contributed to the low diversity of native trees in the designed landscapes.