Fistulina hepatica

Description

Properties

Fistulina hepatica, also called liver mushroom or ox tongue, is a tree mushroom in the liverwort family (Fistulinaceae).

Fistulina hepatica is a xylobiont and lives as a weakling parasite almost exclusively on oaks, rarely also on sweet chestnuts or even more rarely on other deciduous trees such as walnut or ash. Injuries to the tree bark serve as an entry portal for the spores. Inside the trunk, the fungus spreads parasitically, initially hardly harming its host because its life processes remain unaffected. Only the heartwood of the central cylinder – which is dead anyway – is affected. This wood decomposition occurs very slowly as the fungus breaks down the tannin-containing heartwood, utilizing the tannins from the parenchyma cells. Wood decomposed in this way eventually shows brown rot. Since this process proceeds slowly and, due to the preferential tannin decomposition, the structure-giving wood components cellulose and hemicelluloses are almost not attacked at all, trees attacked by ox-tongue are still break-proof and stable for a long time; only late does cube breakage occur. The annual fruiting body appears in June/August to October/November mostly on the lower section of the trunk. Initially it pushes out of the trunk like a tongue, in adult specimens the fruiting body stands out from the growing point as a semicircular or fan-shaped bracket.

In the past, the Fistulina hepatica was known in Anglo-Saxon-speaking countries as “poor men’s beefsteak”, because it was found in abundance in the forests and served as a meat substitute when fried in a pan.

The importance of the oak liverwort as a wood decomposer is low because of the slowness of this process. The usability of the hardwood is on the one hand reduced by the discoloration, but on the other hand it is precisely because of this that it is sought after for some cabinetmaking work. However, if brown rot-induced decay has already occurred, the wood is no longer usable. Ecologically, ox-tongue is considered a weak natural indicator. The ability of this fungus to break down tannic acid, which the tree actually stores as protection against parasites, can make it easier for other xylobionts to colonize the wood and also weaken it through decomposition. One such example is the clapboard fungus, which often colonizes oaks or sweet chestnuts at their base together with the oak liverwort, or as its successor fungus, preferentially.

The reddish liquid contained in Fistulina hepatica flesh colors the trunk wood dark reddish brown due to storage in parenchyma cells, this is known as hard redness or colloquially as chocolate wood. In most cases, only one fruiting body is formed per infested tree. The Fistulina hepatica is also found on already dead oaks and their stumps. It then lives saprobiontically, that is, as a deadwood decomposer. Rarely, the fungus occurs in its anamorphic form. These cushion-shaped, imperfect or conidia fruiting bodies are given the scientific name Ptychogaster hepaticus (Sacc.) Lloyd. Unusually, the accessory fruiting form of the oak liverwort can produce both conidia and chlamydospores, the latter surviving in certain cells of the host, the fibrous tracheids.

1. Growing

2. Identification

3. Consuming

4. Data med, edible