What alternatives does Carson propose to the use of chemicals to control unwanted pests & plants?

Carson proposes an alternative approach to pest control that poses no risks to both the environment and humans. These alternatives are called "biotic controls", and are divided into three specific methods.

The first method would use chemicals found within the insects themselves to repel the insects or trap them. Instead of using a poisonous and harmful chemical, it uses the insect itself to control the pest population. This is an environmentally acceptable means of pest control.

The second method would require sterilizing male insects and introducing them into the pest population. This would gradually reduce the volume of the pest population.

The third method uses both natural bacteria and insect predators to kill off pests. Allowing insects to kill each other off does not harm the environment the way pesticides do.