Alluvial Forests


Description: These specific forest communities are bound to localities which are influenced by water. Such forests can be found on the Dyje river´s narrow flood plain and along small tributaries, where we can find alder stands with stitchworts (Stellaria), as well as fragments of willow scrub in places. These stands are well adapted to occasionally being flooded by the Dyje. The predominant trees are the black alder and the crack willow, but we can still find an abundance of white elm trees here – some of which have reached monumental sizes. Small areas of fen alder stands (alder carrs) can be found scattered around springs in the forest.


jírovec u řeky Dyje pod Hardeggem

Trees which are affected by floods often grow into bizarre shapes


Flora: If we walk in the alluvial forests and alder stands we can find the endangered snowdrop (Galanthus nivalis) and marsh marigold (Caltha palustris), as well as the wood stitchwort (Stellaria nemorum), alternate-leaved golden saxifrage (Chrysosplenium alternifolium), ground ivy (Glechoma hederacea), touch-me-not balsam (Impatiens noli-tangere), hedge woundwort (Stachys sylvatica), tufted hair-grass (Deschampsia cespitosa) and giant fescue (Festuca gigantean). At localities with a stronger nitrogen supply we can also find the stinging nettle (Urtica dioica) and the ground elder (Aegopodium podagraria). The moss layer commonly includes hart’s-tongue thyme moss (Plagiomnium undulatum), river feather moss (Brachythecium rivulare) and the toothed silk moss (Plagiothecium denticulatum), with mosses of the Orthotrichum family growing on the bark of the willows. The morel fungus Verpa bohemica grows in some of these stands early in the springtime.


sněženka podsněžníkSnowdrops 

jarní aspekt v lužním leseThe spring aspect in the alluvial forests


Fauna: The small fragments of alluvial forest are inhabited by a range of species which are bound to the dead wood, such as the rove beetle Siagonium quadricorne and the click beetle Ampedus elegantulus. Rare species which live on the old and damaged trees include the beetle Nosodendron fasciculare. The click beetle Calambus bipustulatus is abundant in the alluvial stands, while the click beetle Selatosomus cruciatus is locally abundant. The musk beetle Aromia moschata and the jewel beetle Agrilus ater are bound to the old willow stands. The jewel beetle Dicerca alni and the longhorn beetle Necydalis major have been found in the trunks of dead alder trees. The occurrence of the weevil Eucoelidinus mirabilis is significant, as it is bound to the spindle tree. The weevil Ceutorhynchus interjectus, which is on the edge of its range in Podyjí, has been recorded on the perennial rocket. Typical birds include the lesser spotted woodpecker (Dendrocopos minor).

Author: Robert Stejskal