This symbiotic association has been so successful that there are now about 20,000 species of lichens, represented in most habitats in the world.
Lichens may be a particularly conspicuous part of the ground cover in the Cumberland Plain woodland at the Australian Botanic Garden and we have recorded a number of species below. Identification may be difficult, requiring fruiting bodies that are not always present and we have photos of a few as yet unidentified specimens.
Lichens form fascinating shapes and structures and a number of broard groups are recognised:
foliose lichens have lobed growth forms
crustose lichens look like thin crusts and are firmly attached over their entire underside
squamulose lichens look like thin flakes or crumbs scattered over the surface
fruticose lichens are erect or pendulous, markedly three dimensional and attached at the base
Colours range from grey to orange, and they occur in a variety of different places. Some grow on dead branches, some on rotting logs, some on the soil and on rocks. Lichens are important in providing soil surface protection against erosion in dry habitats.