The topic of this masterthesis is the influence of grove on dams. Especially the development of certain grove installation techniques at flood control dams in Deutsch-Wagram was observed in 2011. The consequences of willow shrubs on the stability of the flood control dams and especially the root penetration of the dam are exemplified in this work and are explained through biologically and climatologically processes and conditions. Typical for this type of heavily compressed dam with a low percentage of organically substance is the root mat formation of the fine and middleroots on the upper, 35 cm thick layer of the dam. Only few roots reached a depth of a maximum of 65 cm in 2011. In contrast to the 2010 the root penetration, respectively the root mass, declined for the first time since the establishment of the site. The willows was planted in 2007 and 2008. The above ground part of the cultivation displays different characteristics depending on the way of installation, position of the sectors and vertical sequence. Conclusion on the usage and stability of the dam under influence of flood waters can be made depending on the root shoot ratio, the length of the scion, leaf areas and trunk diameters.