The Mëllerdall, as the Luxembourgish valley is called in its native language, offers around 100 km of scenic hiking trails that welcome visitors to explore the geological and natural wonders of Luxembourg. In Bill Bryson’s book “A Walk in the Woods”, he praises Luxembourg as having some of the finest hiking trails worldwide. He noted that “footpaths lead (him) into a cultural landscape of fields, woodlots, farms and villages” and the experience was of “the whole of Luxembourg, not just its trees”.
The most compelling part of a recent weekend in the valley was the company of three, who, in comparison to my little knowledge of what lies in woodlands, are experts in botany, forestry and mycology. Due to their expansive familiarity with the species we came across, we were able to spend two days skipping from plant to mushroom to tree with categorisation books at hand.
Amidst our fascination, we were probably most thrilled to encounter our evening meal. Stockschwämmchen (Latin: Kuehneromyces mutabilis), known as sheathed woodtuft mushrooms in English, make for a delicious dinner when not confused with their doppelgänger, Galerina marginata (also known as: autumn skullcap/ deadly galerina).
Around 200 to 250 million years ago, the sandstone and dolomite layered rocks that we walked between were an ocean bed. What stood out to us the most were the vast rows of holes on the rock surfaces caused by hundreds of years of honeycomb weathering, also referred to as stone latticing, a type of cavernous weathering. This type of erosion often occurs in sandstone or granite rocks. The reason behind this formation is the combination of marine abrasion, wind corrosion and, most commonly, salt weathering. In salt weathering, a saline solution seeps into pores and cracks in the rocks and when the temperature change causes the ice to crystallise, it expands and fractures the stone.