## 2 Materials
### PlanetScope Satellite Imagery and Preprocessing  
In this research, the basis for mapping allergenic tree species is commercial PlanetScope (PS) data. The imagery used in this analysis was obtained from Planet Inc., the global leader in satellite constellations, which operates over 170 orbiting satellites [23]. Many of these satellites are in a sun-synchronous orbit with 4- to 8-band radiance products at 3-4 m spatial resolution. According to [PERSON] et al. [22], the global median average revisit interval of PlanetScope observations is one day, whereby 71.8% of land is acquired with a less than 36 h average revisit interval. In such a way, increased coverage of satellite imagery \begin{table}
\begin{tabular}{c c c c} \hline \hline
**ID** & **Specie** & **Genera** & **Sample Count** \\ \hline \multirow{3}{*}{1} & \multirow{3}{*}{Ash} & _Frazimus Americana_, _Frazimus Exelsior_ & \multirow{3}{*}{2709} \\  & & _Diversifolia_, _Frazimus Ornus_, _Frazimus Exelsior_ & \\  & & _Globosa_, _Frazimus Exelsior_, _Frazimus Angustiifolia_ & \\ \multirow{3}{*}{2} & \multirow{3}{*}{Birch} & _Betula Pubscens_, _Betula Pendula_, _Betula Papyrifera_ & 2808 \\  & & _Platanus_\(\times\)_Acerifolia_ & 2693 \\ \multirow{3}{*}{3} & \multirow{3}{*}{Other} & _Alnus Clutinosa_, _Populus Nigra_, _Carpinus Betulus_ & 3220 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of the allergenic tree species, along with genera/families of the species and a number of samples used for classification purposes. Figure 1: Location and geographic extent of the study area with a PS true-color composite image as the background. The red rectangles represent examples of subset 1 and 2 of urban green areas with protected green areas and cultivated green infrastructures, respectively. acquired from microsatellites provides more opportunities for obtaining images with 0% cloud coverage. PlanetScope satellites have been equipped, depending on the generation of the sensor system, since 2016 with four bands (Blue, Green, Red, Near Infrared--NIR; PS2 and PS2.SD generation), while the new generation--since 2019 (SuperDove; PSB.SD) has enabled eight-bands products (Coastal Blue, Green I, Yellow, and Red-Edge spectral bands are added) [24]. Based on the newly added spectral bands, the Red-Edge band played an important role in improving the accuracy of crop classification, due to the region where the spectral reflectance of green vegetation rises rapidly [35]. For this research, we selected six PlanetScope eight-band PSB.SD images that were acquired in a period between April and July, with 0% cloud coverage. Furthermore, the PSB.SD imagery used in this study (Table 2) included Ortho Tile Analytic (Level 3A) data products which are orthorectified, and preprocessing has been made (i.e., sensor, radiation, atmospheric, and geometric correction). Vegetation indices (VI) derived from RS satellite imagery are useful for evaluating vegetation cover, growth, and other characteristics [36]. Along with the four typical spectral bands (i.e., blue, green, red, and NIR), the PSB.SD sensor provides an additional four multi-spectral bands (see Section 2.2), which are narrowly focused on a particular range of the electromagnetic spectrum, which can be used for conservation, environmental monitoring, and other applications. Therefore, five different vegetation indices were used in this research, including NDVI (normalized difference vegetation index), NDVI (normalized difference water index), EVI (enhanced vegetation index), SAVI (soil adjusted vegetation index), and GNDVI (green normalized vegetation index). These indices provide information on vegetation characteristics such as chlorophyll content, cover, and leaf area [31]. The specific indices used in the research are listed in Table 3.