Exercise 4.3B: Biological Controls

1. Describe how biological control works.

2. Do some research and find an example of a successful biological control. Write some details about this that include: the kind of predator, the pest, and the crop that the grower was trying to protect.

3. Do some research and find an example of an unsuccessful biological control. Write some details about this that include: the kind of predator, the pest, the crop that the grower was trying to protect, and what went wrong to make this unsuccessful.

4. Why might a farmer decide to use chemical controls rather that other kinds of controls for an insect pest?