The lichens are useful to the nature as well as to the human life.

Some of the economic importances of lichens are:

They areregarded as the pioneerswho have inhabited the rocky habitat. The organic acids produced by them disintegrate rocks. The first lichen species is theLichen condelarins.

They areregarded as the soil formerssince it breaks down the hard rocks into soil.Mossesare the successors of thecrustaceous rocks.

It is used asfood by the higher animals. The Cladonia rangiferinais used as the rein deer moss. It contains Lichenin which is a carbohydrate which is similar to the starch.

It is also used by thesmall insectslike mites, caterpillar, snails etcas source of food. Some of the species of lichens areAspicilia calcareaandLecanora saxicola.

Some of the lichens are alsoused as the food by the human beings. Example is theCetraria islandicaalso known as the Iceland moss.

It is also used in thetreatment of many diseases like diarrhea, jaundice, fevers, epilepsy, hydrophobia etc. it is also used in the preparation of culture media.Parmelia saxatilisis used to cureepilepsy. TheUsneaandEvernia furfuraceais used asastringents.Cladonia pyxidatais used to curewhooping cough.

It is used forcolouring the fabricsandpaints. Lichensaresource of litmus whichare used in thelaboratoryit isproduced from the lichen Roccella tentoria.

It is used for theproduction of perfumessince it can retain the power of retaining the odor it is used.

It is also useful in thetanning, brewingand distilling.