For instance, what are those green masses growing on your trees? Those growths could be either lichens, moss or algae, and the good news is that none are cause for alarm. Because they usually grow ...

For instance, what are those green masses growing on your trees? Those growths could be either lichens, moss or algae, and the good news is that none are cause for alarm. Because they usually grow ...

Lichens grow on the out skirts of vegetation, as pioneers of the plant world; preparing the way for moss, fern and flowering plant. They are most intimately in touch with the substratum in its ...

While they're sometimes mistaken for moss, lichens are miniature ecosystems made up of a fungus and an algae or bacteria that can make energy from sunlight, living together in one body.

There are some 15,000 varieties of lichens that cover around 10% of the Earth’s surface. Not to be confused with moss, lichens are their own thing — and they actually aren’t plants at all.

Moss walks, moss talks, moss movies, crafting moss-themed Valentines (it's hard to resist "I Lichen You A Lot" puns), which students look forward to every year. Some students dress up as moss.