TimeStamp- date and time of measurement (format YYYY-MM-DD HH:MM:SS; 24 Hours) All other columns- sap flux density in meters per hour, following removal of bad data and setting negative values to zero. One column per tree stem. Column headers (e.g.: 30233_1a) correspond to the identification number of the tree (e.g.: 30233) and stem number (e.g.: 1) on which the measurement are made. If more than one probe was installed on the same tree stem, these are distinguished by letters (e.g.: a).