Succession
Primary and secondary succession differ in many ways. Primary succession takes place on land where there has been no previous growth of vegetation and secondary succession occurs on land where there has been previous vegetation growth. There is also no substrate in primary succession, but in secondary the soil and seed makes up the substrate. Some examples of places where primary can occur are lava rock, bare rock, or after a glacier recedes. Some examples of where secondary could occur are after logging, and abandoned agricultural field, or following a natural disaster.