In Britz we study the water consumption (evapotranspiration) of important commercial tree species since 1974. The main feature are the nine large-scale lysimeters, installed at a depth of over 5 m with a surface area of 100 m² (10x10 m) each. They are planted with 0.3 ha experimental stands of Scots pine (Pinus sylvestris) (3 lysimeters), European beech (Fagus sylvatica) (2), European larch (Larix decidua) (2), and Douglas fir (Pseudotsuga menziesii) (2) spaced corresponding to the forestry practice at that time. About 15 years ago one Larch lysimeter was clear-cut and replanted with sessile oak (Quercus petraea). On two Scots Pine lysimeters, European beech was planted building now the understory. The areas surrounding the lysimeters were planted in a similar fashion. Seepage water collecting at the bottom of the lysimeter flows down a shaft and is measured mechanically by a tipping counter and registered electronically. Soil moisture is measured with probes to a total depth of 5 m. Precipitation in the open field and the stand is recorded with Hellmann rain gauges. In addition, the station is equipped with devices assessing individual tree water transport and growth (sap-flow sensors, dendrometers), an Eddy-Fluy-Tower and much more. The studies are aimed at revealing the effects of different tree species and mixtures on the ground and landscape water balance. Moreover, the effects of drought on tree performance and tree-internal water budgets are of interest. However, recently we added acoustic monitoring, a pollen collector, regular UAV flights to our assessments and are always open to more co-operations.