What is the first stage of ecological succession?

The first stage of succession involves pioneer species. 

1. In primary succession, pioneer plants are those that can grow without soil, such as lichens. 
2. Lichens begin breaking down a rock. 
3. Seasonal cycles of freezing and thawing form cracks in the rock. 
4. The dead remains of lichens and dust fall into the cracks. 
5. Mosses may begin to grow. When mosses and lichens die, they form parts of soil.
6. Slowly, enough soil forms for small shrubs to grow. 
7. The roots of the shrubs break up more rock and more soil forms.
8. Larger plants are able to grow. 
9. Eventually, a mature community exists where once there was only a bare rock. 

Further Reading  – 

1. Species in News
2. Types of Rocks
3. Rock Cycles