# Near-Real-Time Detection of Insect Outbreaks in Urban Trees Using a PlanetScope Time Series
## 5 Conclusions  
Five main conclusions can be drawn from this study. First, the use of PlanetScope imagery enabled the study of small urban areas due to its high spatial resolution. Moreover, the availability of daily data allowed for the collection of highly accurate information regarding the spectral responses of the analyzed areas. Even if PlanetScope imagery requires a paid subscription, the cost is relatively low compared to the operational advantages it provides. With an annual investment of approximately EUR 12,000, it is possible to access up to 30 million km\({}^{2}\) of imagery. While free options such as Landsat and Sentinel-2 are available, PlanetScope offers significant advantages in terms of spatial and temporal resolution, making it a valuable choice for projects requiring detailed and frequent monitoring. This balance between cost and enhanced capabilities highlights the practicality of PlanetScope for large-scale, high-resolution studies. The use of PlanetScope imagery for detecting _T. parvornis_ is a novel approach that has yielded promising results. Second, ground-based georeferenced data were successfully integrated with remote-sensing techniques, enabling the extraction of precise information from satellite images in areas of interest. This method allowed for the analysis of the spectral responses of _P. pinea_ alone, excluding other species in the area. Third, the RDVI index proved to be effective in distinguishing between infested and healthy trees. Although previous studies on _T. parvornis_ in Italy utilized different indices, the application of the RDVI to this specific phenomenon yielded particularly satisfactory results. Fourth, a threshold was identified to classify healthy versus infested plants. This threshold represents a valuable tool in the management of _T. parvornis_, as it is easily applicable in various urban contexts. To effectively counteract the invasion of _T. parvornis_, further studies in this direction are necessary. Among future developments, it would be interesting to develop a technique to identify markers that allow for intervention before the plant dies. In this sense, sharing more information from stakeholders on the health of the plants before infestation and the timing of treatment cycles could enhance the interpretation of the phenomenon's dynamics. Continuing to conduct annual ground surveys will expand the volume of data and knowledge regarding the current state of the plants, as doing so is essential for refining remote sensing-based work and obtaining more accurate results. Conceptualization, data curation, methodology, formal analysis, and investigation, V.F., S.F. and F.P. ; writing--original draft preparation, V.F. and S.F. ; writing--review and editing, V.F., S.F., F.P., P.D.F., G.D., M.M. ([PERSON]), M.M. ([PERSON]), M.O., G.C. and B.L. ; validation, A.C. and B.C. ; supervision, M.M. ([PERSON]), M.M. ([PERSON]), M.O., G.C. and B.L. All authors have read and agreed to the published version of the manuscript. This study was supported by the following projects: PNRR, a project funded under the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.4--Call for tender No. 3138 of 16 December 2021, rectified by Decree No. 3175 of 18 December 2021 of the Italian Ministry of University and Research funded by the European Union--NextGenerationEU; Project code CN-0000003, Congressional Decree No. 1034 of 17 June 2022 adopted by the Italian Ministry of University and Research, CUP H73C22000300001, Project title \"National Biodiversity Future Center--NBRC\". FORWARDS. H2020 project funded by the European Commission, number 101084481 call HORIZON-CL6-2022-CLIMATE-01-05. SUPERB. H2020 project funded by the European Commission, number 101036849 call LC-GD-7-1-2020. MONIFUN. H2020 project funded by the European Commission, number 101134991 call HORIZON-CL6-2023-CircBio-01-14. NextGenCarbon. H2020 project funded by the European Commission, number 101184989 call HORIZON-CL5-2024-D1-01-07.