| Summary: | Black Locust/Robinia can play an important role in land reclamation due to its pronounced nitrogen fixation capability, fast initial growth and relative high drought tolerance. Hence, we set up a trial to test 12 Black Locust clones and three provenances growing on sandy overburden material within the open cast lignite mine <i>Welzow-Süd</i> (South Brandenburg) in March 2014. Since then, biomass growth of the Black Locust trees was examined and physiological performance was studied on several occasions using chlorophyll a fluorescence and Dualex<sup>®</sup> measuring technique. Plant physiological measurements revealed differences in photosynthetic vitality (PI<sub>ABS</sub>), although the PI<sub>ABS</sub> values followed a similar pattern and sequences across the plot. While the genotypes <i>Fra3</i> and <i>Roy</i> show the highest photosynthetic vitality, the clones <i>Rog</i> and <i>Rob</i> display the lowest PI<sub>ABS</sub> mean values. Chlorophyll and phenol content as well as the nutrition supply of the test trees vary depending on their origin and site conditions. The annual biomass growth rate corresponds to photosynthetic vitality and both depend on weather conditions during the growing season. After six years, the growing biomass amounts to 14.7 Mg d.m. ha<sup>−1</sup> for clone <i>Rob</i> and 44.8 Mg d.m. ha<sup>−1</sup> for clone <i>Fra3</i>, i.e., 2.5 to 7.5 Mg d.m. ha<sup>−1</sup> year<sup>−1</sup>. Our data demonstrate a good correlation between biophysical parameters and biomass growth. We, thus, infer that physiological measuring methods can be combined to strengthen predictions regarding the physiological performance of Black Locust origins.
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