In supplement to the
monitoring project described above, an investigating of the
lichen flora on walls of medieval churches is taking place. The
walls of 125 churches, 25% percent of all pre-1550 churches in
the country, were visited in 1999 and 2000 during field
trips. An investigation of species presence was made, without
noticing their quantities. There is only the aim of estimating
the biodiversity at the present moment.
About 25 of all 700 lichens known from the country are restricted
to church walls, including 10 red listed species. During the
investigation, 173 lichen species were found. The number of
species per church varied from 10 to 77. Especially walls of
volcanic tufa have a valuable lichen flora.
An informative brochure about algae, mosses and lichens on
monuments has been prepared in cooperation with the National
Trust (RACD).
Lecanora pannonica covers a wall made of
volcanic tufa rock. Some church towers are completely pale
coloured due to the abundant presence of this species.
Dirina
stenhammari is a characteristic species for shaded north
faced walls, growing on mortar. On freshly cleaned (sandblasted)
walls this species returns as first, because the soredia have
been 'impregnated' by the cleaning process.