Fluorescence is a signature of photosynthesis (see chapters by Govindjee (2004) and others in Papageorgiou and Govindjee 2004). If I did not understand fluorescence, I had to conclude that I did not understand photosynthesis. I returned to Würzburg in a state of confusion. I started wondering whether my inexplicable Namibian, New Zealand and alpine observations had something to do with my early observations on light scattering by leaves and on photo-protection of plants as seen by Barbara Demmig. Time proved these forethoughts right. Fig. 8 Fluorescence equipment ready for experimentation near the beach north of Swakopmund, Namibia. In the background brown lichen

vegetation (Teloschistes species) and ocean. Courtesy Otto Lange, Würzburg Forest EPZ5676 purchase damage In the late 1980s, the German public was much worried by alarming reports in the press that our beloved forests were about to die. Polluted air was blamed. I had read Saracatinib mw in Parkinson′s law that it is not the task of the botanist to eradicate the weeds. It is sufficient for him to identify them. I wished to identify the culprits. Sulphur dioxide was a candidate. Being an elected member of Deutsche Akademie der Naturforscher Leopoldina in East Germany, today National this website Academy of Sciences of the Federal Republic of Germany, I needed a valid visa to visit the German Democratic Republic where forests were dying along the border

to Czechoslovakia, now the Czech Republic. Visa was issued for the city of Halle, the site of Leopoldina. Visits to other places were not permitted. Nevertheless, I collected branches of Picea

excelsa illegally from trees near the village of my childhood, not far from the border to the Czech state. The analysis of needles from fir trees which 50 years earlier had been property of the Heber family made me admire the tenacity of our trees. High sulphate concentrations in surviving needles were the result of the oxidation of sulphur dioxide, which was emitted by our Czech neighbours, had crossed the border with the so-called Bohemian winds and had entered the needles. Tree death not was understandable. Tree survival was the miracle (Kaiser et al. 1993; Elling et al. 2007). SO2 was identified as a culprit. This conclusion was not new. It confirmed conclusions from research work performed about 100 years earlier at Tharandt, next to the village of my childhood, when trees had died in Saxony as industrialization had dramatically increased the burning of sulphur-containing coal. A postdoc, Sonja Veljovic-Iovanovic, doing good work on SO2 (Veljovic-Jovanovic et al. 1993), did not make my life easier when I protected her, a proud Serbian national, in her private war against German public opinion during the Balkan conflict. Work on forest damage was extended to include ozone which is formed in bright sunshine from a reaction between nitrogen oxide and oxygen (Luwe and Heber 1995).