Even though Crater Lake contains very few nutrients it is home to colonies of moss as well as bacteria at the lake floor.  The moss colonies are a complex ecosystem which may be 4,000 years old or more.  “Deep Moss” as the moss colonies are called, grows very slowly and over a very long period of time within a very nutrient poor environment.   The community of moss is composed of moss which is anywhere from 3 feet to 20 feet thick, and live 100 to 420 feet down.   The species is called Drepanocladus and lives on the shelf around Wizard Island and on the steep vertical walls of the caldera.   Deep moss has a mass large enough to crush your house.  The scientist’s uses the pollen from the moss to carbon date it.   The moss beds are full of holes which scientists are still trying to figure out.   The moss beds help to monitor the effects of global warming.  The moss grows beyond the depth that normal photosynthesis could occur, however, because of the clarity of the water in Crater Lake, the zone in which photosynthesis could take place extends much deeper than most other lakes in the world.  Scientists believe that if the water in Crater Lake became compromised then the moss would begin to grow in shallower water to enable it to get to the light.   The growth levels have been compared to the growth levels of 20 years ago and the moss has remained at the same depth which leads scientists to believe that the clarity of the lake has remained constant.