Ions Identified By Vocus.csv contains the information of ions identified by Vocus from the emission of the downy birch tree. It consists of the m/z value, mass defect and molecular formula. The mass defect plot seen in the paper uses data from this file. Emission Rate.csv file contains the emission rates of 49 ions that are further discussed in the paper. The emission rates are converted from the raw data measured by the Vocus. The conclusions drawn and mentioned in the article use the data from this file. The gaps seen in the dataset are points of calibration which have been removed to include only the emissions observed by Vocus. Environmental Parameters.csv file consists of environmental parameters measured inside the branch chamber. Ambient Parameters.csv file consists of environmental parameters observed in the ambient environment in Hyytiälä. It was downloaded from FMI open weather data. The ambient weather data was taken from https://en.ilmatieteenlaitos.fi/download-observations on 22-04-2021. All the time series data has a time resolution of 20 minutes.