Friday, December 5, 2014

White lichens, green mosses, and Swedish Christmas...

It is Swedish culture time!

During the four weeks before Christmas, many Swedes light four advent candles, one at a time for four Sundays before Christmas Day. Traditionally the boxy advent candle holder are filled with a puffy white lichen from the Swedish forests. These days, more and more people switch to less fire prone materials in their candleholders, but the tradition still exist, and the lichens are for sale in regular supermarket and garden centers during the fall.
Swedish advent candles. Image source: Photoakuten.
Unfortunately, one of the old-fashioned names for these lichens are 'white moss' ('vitmossa'), which is also the correct common name for the very common peat mosses in Sweden. The correct name for the most commonly used lichen for advent is 'fönsterlav' (= window lichen) or 'renlav' (=reindeer lichen) in Swedish. This leads to a lot of confusion and errors, but also a lot of education opportunities in many Swedish stores and homes at this time of the year. 

In her fantastic and already classic video, Mirja Hagström explains the difference between a peat moss (Sphagnum) and a lichen (Cladonia, known as cup lichens and reindeer lichens), and what 'vitmossa' really is. It is in Swedish, but with somewhat Swenglish subtitles. Enjoy!

Of course it is not only Swedes that are confused about mosses and lichens, but also Americans.  Remember this older post from this blog? Reindeer moss is a lichen, not a moss

Calling lichens mosses is about as farfetched as calling a sea star an octopus.  The two groups are not at all that closely related.  Mosses is a group on the green land plant tree of life.  Lichens are fungi that live in symbiosis with algae. Of course in the old times lichens were often called 'moss', but to use that name today would just be confusing since we know better and have better, more correct names for lichens.  There is no need to perpetuate or introduce extra confusion in botanical words.

Some stores have started to use both names (vitmossa/fönsterlav) on their packaging, but then they still accept the name vitmossa for this lichen.  It would have been better to call it 'fönsterlav (formely known as vitmossa)'.  Some stores hav also started to sell any green moss under the name 'grönmossa' (=green moss), which is about as specific as saying 'red flowers' on a package.  All mosses are green when alive, even 'white moss', i.e. peatmosses, even if they can also have red, brown and yellow tones.

For examples of Swedish advent products with both mosses and lichens, see: