Figure 4 Ash tree distribution and EAB presence in China from 1900 to 2019. (a) The green background indicates the range of native Asian ash species which are widely distributed in all 34 provinces, provincial cities, or regions in China. Red, black, yellow, and blue quadrants indicate locations where exotic green, white, velvet, or European ash trees were planted, respectively. Black circles indicate the presence of EAB infestations. (b) Relationships between the plantings of non-Asian ash trees and EAB outbreak in China from 1900 to 2019. The insert figure represents an enlarged display of ash plantings from 1900 to 1970.