Fig. 2From: Combining WV-2 images and tree physiological factors to detect damage stages of Populus gansuensis by Asian longhorned beetle (Anoplophora glabripennis) at the tree levelExamples of different damage degrees of Populus gansuensis caused by ALB. (a) green-stage; (b) yellow-stage; (c) grey-stage; (d) dead treeBack to article page