English: Elder Whitewash (Hyphodontia sambuci). Alongside the cycle route, between 1068180 and 1157989, some Elder Whitewash was visible, in the form of the white crust that is shown here. This is a common species, and it can be found all year round.

Here, it was growing on the kind of wood that is indicated by its common name, but it does, especially in warmer climates, occur on other hosts. 933080 is another species that favours elder (Sambucus) as a host, and some fruiting bodies of that species were growing on the same piece of wood.

[Many online photographs of this species show a far smoother surface, but according to "Fungi of Switzerland – Vol 2" (Breitenbach/Kränzlin), in which this species is listed under the synonym Lyomyces sambuci, the surface is "tuberculate to slightly verrucose", i.e., it has small bumps or warts. In addition, when the fungus is dry (which was not the case in my photo), its surface is often fissured. See http://www.indexfungorum.org/Names/SynSpecies.asp?RecordID=298800 (at Index Fungorum) for the current name, and for synonyms.]