## 5 Conclusions  
In this study, we proposed a new perspective based on spatiotemporal change detection for the tree-scale PWD detection in a complex landscape with mixed forest and fragmented land cover. The approach captured spatial and temporal patterns of the PWD-induced wilting through a bi-temporal analysis and a spatial enhancement. The results showed that the proposed method can effectively distinguish wilted pine trees from discolored deciduous trees, sparsely vegetated regions, and many other objects with which they are easily confused. The user's accuracies for the proposed method were significantly higher (81.2%) than those for the single-date classification (67.7%). By not limiting ourselves to a specific method, we are more focused on proposing a spatiotemporal feature extraction strategy that effectively address targets that cannot be distinguished solely by spectral information, with a goal toward advancing research on remote sensing monitoring of forest pests and diseases. Conceptualization, B.Z. and H.Y. ; methodology, B.Z. ; software, B.Z. ; validation, B.Z. and W.L. ; formal analysis, B.Z. ; investigation, B.W., Z.H. and H.S. ; writing--original draft preparation, B.Z. ; writing--review and editing, B.Z. and H.Y. ; supervision, W.H. ; funding acquisition, W.H. All authors have read and agreed to the published version of the manuscript. This research was funded by the Strategic Priority Research Program of the Chinese Academy of Sciences (grant number XDA19080304), by the Major Emergency Science and Technology Project of National Forestry and Grassland Administration (grant number ZD202001), and by the National Natural Science Foundation of China (grant number 42071320). Data Availability StatementData sharing is not applicable to this article. The authors gratefully acknowledge Planet Inc. for providing the planet images through their research and education program. We thank [PERSON] and [PERSON] for help with the fieldwork. In addition, [PERSON] would like to thank [PERSON] for the help in typesetting. We would like to thank the reviewers for their helpful and constructive comments, which have improved the paper. The authors declare no conflict of interest. * (10) [PERSON]; [PERSON]; [PERSON] Remote sensing of forest insect disturbances: Current state and future directions. _Int. J. Appl. Earth Obs. Geoinf._**2017**, _60_, 49-60. [CrossRef]
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