Sy Rocks

Located on the territory of the former municipality of Vieuxville, at the eastern end of the Calestienne, the Sy Rocks consist of a succession of rock outcrops extending over several hundred meters on the right slope of the Ourthe valley, just upstream from the hamlet of Sy. It is less than a kilometer from the famous archaeological site of Palogne. At this location, the terrain is very steep and primarily faces south and southeast. These rocky slopes, unsuitable for agriculture, are largely covered by particularly interesting forest vegetation: calcareous beech forest, calciphile oak-hornbeam forest with bird's-nest orchid (Neottia nidus-avis), lovely wood (Daphne mezereum), and large-flowered helleborine (Cephalanthera damasonium), ravine maple-elm forest with hart's-tongue fern (Asplenium scolopendrium), xerophilous Famennian oak-hornbeam forest with service tree (Sorbus torminalis) and flexible hairgrass (Deschampsia flexuosa) on a more schistose substrate. Additionally, at the foot of the slope, on the alluvial bench, the ash-alder forest is home to yellow gagea (Gagea lutea), false anemone (Anemone ranunculoides), and solid corydalis (Corydalis solida). The limestone rocks host remarkable flora including elements of rocky lawn with pale fescue (Festuca pallens) and xeric lawn with blue sesleria (Sesleria caerulea) and ciliate melica (Melica ciliata). The western part of the slope, once occupied by a mixed stand of hardwoods and pines, underwent restoration work in 2010 by the LIFE Hélianthème project. Since then, the dry lawns that were maintaining in a fragmented state have considerably expanded and enriched with characteristic species of this habitat, such as lily-flowered starry (Anthericum liliago), woundwort (Anthyllis vulneraria), small-oak germander (Teucrium chamaedrys), pigeon scabious (Scabiosa columbaria), yellow helianthemum (Helianthemum nummularium), and many others. This cleared area was established as a public domain nature reserve in spring 2015, covering a total of 5.3 hectares. However, the entire site is included in the Natura 2000 network.

Public access: Some areas of rocks are threatened by the invasion of the exotic invasive shrub Cotoneaster horizontalis.
Type: Site of Great Biological Interest (SGIB)

La biodiversité en Wallonie