A very commen Cladonia's that grows on almost every
underground.
It is hard to distinguish them from other Cladonia's
But the tallus is relativly smooth.
cladonia fimbriata on a roof made of reed
On a roof one can find Cladonia fimbriata on reed
Cladonia wonderland on a roof made of reed, one can see
Cladonia fimbriata, Cladonia glauca and Cladonia floerkeana.
lichen
Lichen can grow on places were the green plants can't survive:
They can be found on the Southpole, in the desert,
and high in the mountains.
symbiotic
Lichen consist of a fungus and an algae, its a symbiotic relation:
The fungus can't survive without the algae, but the alg can live
without the fungus. Most lichen live from the air, they don't
have roots to take up nutrients.
The small roots (rhizines) only function is to attach the lichen
to the substrate. Lichen are very sensitiv for (air)pollution.
Cladonia wonderland on a roof made of reed, one can see 
