Figure 1

LC-DAD-isoplots of 8 bark extracts, which represent all main UV peaks observed among the 18 analysed extracts. The analysis was performed with reverse phase chromatography, where hydrophilic compounds elute first and the more the hydrophobic compounds at higher retention times. UV wavelengths is shown on the y-axis and the high-performance liquid chromatography (HPLC) retention time on the x-axis. The colour represents a relative concentration of the UV absorbing compounds where red = high concentration, yellow = medium concentration, blue = low concentration/absence. S1-S: spruce1 summer; S1-W: spruce1 winter; P-S: pine summer; P-W: pine winter.