• Insecticides such as DDT are sprayed on farm crops to keep insects from destroying them.On the Farm image by mhiser from Fotolia.com
  
  Anywhere humans live, pests are not far away. Food, gardens and refuse are a natural draw for them. Keep food covered and put away, secure lids on all trash cans and maintain a clean house. This will help to fight pests, from insects to larger animals, such as rodents and raccoons. When stronger methods are needed, several products are used to deter or destroy pests.
  
  

Repellents

• Repellents are often used in the garden, lawn and around the outside of a home. Repellents emit an odor on the property or lace plants with an unpleasant taste in an effort to drive pests away from the yard. Devices such as sound generators, claim to drive off unwanted pests by emitting a high-frequency, unpleasant sound that cannot be detected by humans. Granule repellents have a kitty litter-like consistency and are laced with the urine of a predator animal, such as a fox. These can be shaken over plants and around garbage cans to drive off pests.
  
  

Sprays & Gases

• Pesticide and insecticide sprays are commonly used to ward off pests within the home and to kill off infestations. Sprays exist that kill several types of insects, from ants to roaches to spiders. They work as spot killers, sprayed directly on insects, and may also be sprayed around baseboards and cupboards. Gases and fogs to treat large insect infestations can be used by the homeowner or executed by a professional exterminator. These usually require vacating the house during fumigation and returning when it is safe.
  
  

Traps

• Traps are available to capture nearly any size pest, from ants to raccoons. Traps for insects often contain glue to capture them, rendering them unable to move. Traps used to catch and kill rodents have come a long way from the simple, spring-loaded mousetrap. Modern mousetraps are often boxes, or "houses," in which a small amount of food is placed. The mouse climbs in, it drops down and cannot climb back out. Live traps for larger animals, such as raccoons, work in a similar way. The animal is drawn in through an opening, but cannot escape once caught. This way, the animal is still alive and can be safely removed.
  
  

Bait

• Poisoned bait is sometimes used to destroy rat populations. This method has been used for centuries to kill off dangerous predator animals, such as wolves. Meat that has been poisoned is consumed, and the animal dies. This method is not successful, however, if any other food source is available. If something else is around to be eaten, such as garbage, the rats will eat that. This method is also dangerous for any other animals, including pets, that could eat the poison instead.