A globally rare mushroom grows in the Sihlwald forest

"The discovery of the lemon-yellow tramete shows that the Sihlwald is on the right track," explains Stefan Blaser, who is responsible for the national data and information center for Swiss fungi SwissFungi at the Swiss Federal Institute for Forest, Snow and Landscape Research WSL. He is referring to the fact that the Sihlwald has been slowly developing into an original natural forest since 2000. As such, it is largely left to its own devices, creating deadwood that also offers rare species an original habitat.

Rare beyond the country's borders

Stefan Blaser recently discovered the bright yellow, rare mushroom in the Sihlwald forest east of the Sihl. This is only the sixth discovery in Switzerland - the previous locations were in Emmental, near the Thal Nature Park and in Schmitten in the canton of Fribourg. According to Stefan Blaser, Antrodiella citrinella is also rare in neighboring countries: "In Germany, 18 finds have been registered, all in the south of the country. In Austria, the official database only has one record".

A complex interplay

Antrodiella citrinella primarily needs decaying, thick dead wood to develop, says fungi expert Blaser. However, this alone is not enough for the sponge-like looking fungus: "The lemon yellow tramete only grows where the much more common red-edged tree fungus decomposes the wood," explains Blaser. The relatively rapid death of the fungus also makes it difficult for Antrodiella citrinella to spread. "When the colonized piece of dead wood decays, it needs a new one to survive. The citrinella spreads by air with the help of spores, most of which do not travel very far. They must therefore find a suitable breeding ground in the immediate vicinity," explains Blaser. "Due to its rarity, however, even experts know little about the yellow fungus overall," admits Blaser. One thing is certain: without dead wood there is no red-edged tree fungus, and without it there is no lemon yellow fungus.

Further information

Bianca Guggenheim
Tuesday, March 14 1 - 3 p.m.
Communications, Zurich Wilderness Park Foundation
Tel. 044 722 55 22
bianca.guggenheim@wildnispark.ch