Search the website

… by substrate

The groupings in the menu below are general and show the most common substrates for the listed lichens. It should help narrow down the species you have, particularly when used in conjunction with the chemical spot tests. There are always ‘exceptions’ or individuals trying their hand at another substrate! Bark acidity is variable as it is influenced by bird droppings, local rain fall and wounds in the bark. To describe rock substrate I refer to the silica content of the rock as chemically the terms ‘acid’ and ‘basic’ have no meaning here. There is no such thing as an ‘acid’ or a ‘basic’ rock. The terms ‘acid’ and ‘base’ are reserved to describe bark pH where the terms have a chemical/biological meaning that makes sense to lichens. Being able to associate a lichen with a substrate plays an important part in the field identification of a species. For example, Caloplaca ferruginea and C. crenulata look identical in the field under a hand lens, yet C. ferruginea is only found on trees whereas C. crenularia is only found on silica rich rocks