Oakmoss

Evernia prunastri is a species of lichen in the genus Evernia in the family Parmeliaceae. The species is also known as oak moss. Evernia prunastri is native to the Balkans, Eastern Europe, France and northern Africa (Morocco).

Extracts from oak moss contain 2-3% Evernic acid, atranorin, chloratranol, atranol, evernic acid, usnic acid, divaricatic acid, lecanoric and other lichen acids, waxes, resin, essential oil and polysaccharides.

The lichen species varies in colour from yellow-green, grey-brown, yellow-brown to blue-grey. It grows shrubby on acidic bark of deciduous and coniferous trees, especially on maple and oak (hence the name), grows up to 10 cm in size and consists of up to 0.5 cm wide net-structured bands with a light-coloured underside. The vegetation body of the plant is reminiscent of the shape of elk antlers. In places Evernia prunastri covers the flanks of the trunks with a dense carpet of lichen.

Atranorin is the most common substance found in lichens and mosses. Known sensitizing substances are sesquiterpenlactones, whose chemical relationship to the strongly sensitizing ingredients of composites has been known for a long time.

Allergic reactions to oak moss are known. The sensitizing potential is estimated to be very high,

Eichenmoos absolue has been in the epicutaneous test series (e.g. fragrance mix) since 1980 and is tested individually if the mixture has led to a positive reaction. Sensitizing potency: Weak to medium strong. Sensitisation frequency: Occasional.

Eichemoos is collected by hand and pressed into bales. Extracts of oak moss were already used in ancient times to embalm corpses.

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