Summary 7 How Ecosystems Change

In this summary we will talk about of how the ecosystems change.
An example is the Farmland to forest. 
First an abandoned farm the first year 
a comunity of crabgrass, insects and mice,
invades the field were corn once grew.
The seccond and third year
Tall weeds such as asters, ragweed, and tall grasses grow among the crabgrass. It can easily survive in the shade cast. The rabbits and seed eating bird move in.
Four to Six Year Later
The hot, dry field of tall weeds provides a perfect environment. More birds join the community.
Twenty Five Years Later
A pine forest has replaced the old farm field. Larger animals like raccoons and foxes begin to visit.
one Hundred Years Later
The forest is now mostly decidius trees. These trees are habitats of many different kind of animals.
Examples of pioneer species are weed, birds, insects, plants