In the upper reaches of the Lech, mainly coarse sand and gravel is deposited on the banks. This soil can store almost no water, and although the great waters of the Lech are in close proximity, drought is the characteristic of the riparian forests on the upper Lech. Lavender willow, purple willow, and drought-resistant willow species are spreading. German tamarisk is a survival specialist on the Tyrolean Lech. It has decisive advantages over other plants in the regular flooding. A wide root system anchors it in the ground and its branches are very elastic, so that it is not washed away even during major floods.