Tree size preferences of three epiphytic lichens
Victor Johansson1,2, Karl-Olof Bergman1, Håkan Lättman1,3 & Per Milberg1
Division of Ecology, Linköping University, Sweden, 2Current address: Department of
Ecology, Swedish University of Agricultural Science, Uppsala, Sweden 3School of Life
Sciences, Södertörns University Collage, Sweden
1IFM
Introduction: Old growth deciduous forests have
declined all over Europe and old trees have become
scarce. Quercus robur can reach a considerable age
which makes them an important substrate for many
epiphytic lichens, including several red-listed species.
Aim: Describe the tree size preferences of three
epiphytic lichens, known to represent different stages of
the lichen succession on Q. robur.
The probability of occurrence and different degrees
of lichen cover
Method: The quantity of Parmelia sulcata, Chaenotheca
phaeocephala and Cliostomum corrugatum were
recorded on 858 Q. robur with a CBH between 17–558
cm at two sites in southeastern Sweden.
Data analyses: Effects of CBH were were descried with
logistic regressions. The CBH needed for 50 %
probability (P50) of lichen occurrence and abundance
was estimated.
Result: Parmelia sulcata showed a negative relationship
with increasing CBH. The P50 for occurrence of C.
phaeocephala was 176 cm, while for C. corrugatum
corresponding value was over 300 cm. For the cover
>100 cm2 the CBH for both C. phaeocephala and C.
corrugatum had to reach about 400 cm before before
reaching P50.
Conclusions: Different lichen species have different
tree size preferences. Quercus robur have to reach a
considerable size before some species are able to
establish. This highlights the importance of old Q. robur
for the survival of demanding lichens.
Acknowledgements: We thank Stiftelsen Oscar och Lili Lamms Minne for financial support, and
the land owners Henric Falkenberg of Brokinds gods and the municipality of Linköping who allowed
us work on their land.