| Pioneer species grow quickly when an area is disturbed. Each square meter of healthy soil could contain as many as 1000 dormant seeds. When the vegetation is cleared, many of these seeds sprout immediately. If the vegetation is cleared and the topsoil is also disturbed or relocated, the area remains bare and is susceptible to severe erosion. |
Flowers which provide food for insects are common in early stages of succession. Photo by Maya Walters. |
| The grasses that move in as pioneer species are often thought of as weeds, the subsequent growth of shrubs are considered undesirable "brush". But without these intermediate stages, the disturbed habitat can't return to a natural forest. For example, in temperate forests, if the shrubs are not allowed to grow, insect pests turn to feed on young trees instead. This has happened in many places where trees are replanted after an area is clearcut. Large quantities of pesticides are then brought in, polluting the soil and water and altering the natural ecosystem even further. |
ecological succession -- page 3 of 4
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related topics
[plants] [soil] [seeds] [pests] [deforestation & overcutting] [pollution]
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return to the forests through time article