In this article we will discuss about:- 1. Meaning of Lichen 2. Types of Lichens 3. Reproduction 4. Economic Importance. Meaning of Lichen: Lichens (Fig. 200) constitute an extraordinary group of mostly grayish-green plants widely distributed all over the world. They grow on rocks, tree-trunks, dead wood and on ground, and can withstand extreme temperature. […]