English: Primary succession is the development of soil and life in an area without topsoil. For primary succession to begin, an event must render an area void of plant life and soil. (1) After a volcano or glacial retreat, bare rocks are left. (2) Lichens and mosses grow on the rocks, then the rocks are slowly broken down as plants grow over them and a soil layer is formed from dead plant material. (#) Grass starts to grow with the lichen. (4) Taller grasses and perennials thrive. These species are replaced by new vegetation in the following succession, which happens gradually: (5) low shrubs, high shrubs, (6) shrub-trees, (7) short trees such as pines, and (8) high trees. The area eventually becomes covered in forest and remains that way. The succeeding plants do not all come at once, but as taller plants thrive, smaller plants are outcompeted as their light source is blocked by taller plants; they eventually die and are replaced by taller plants.

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