Liking lichens around the Rock River
Lichen are plentiful around the Rock River, as seen in this video. Press play and then click the "Full screen" button in the bottom right corner of the video window for a larger view.
Not only can lichens live anywhere on earth, the durable organism can survive unprotected in space, according to Wikipedia:
Launched on a Russian Soyuz rocket and directly exposed to the vacuum of space with its widely fluctuating temperatures and cosmic radiation for 15 days, the lichens were brought back to earth and found to be in full health with no discernible damage.
When growing on mineral surfaces, some lichens slowly decompose their substrate by chemically degrading and physically disrupting the minerals, contributing to the process of weathering by which rocks are gradually turned into soil. While this contribution to weathering is usually benign, it can cause problems for artificial stone structures. For example, there is an ongoing lichen growth problem on Mount Rushmore National Memorial that requires the employment of mountain-climbing conservators to clean the monument.
Victorian-era English writer John Ruskin had kind words for lichen: "Sharing the stillness of the unimpassioned rock, they share also its endurance; and while the winds of departing spring scatter the white hawthorn blossoms like drifted snow, and summer dims on the parched meadow the dripping of its cowslip-gold... far above, among the mountains the silver lichen-spots rest, star-like, on the stone."