The most common natural rat repellent is peppermint oil. To be effective, the oil must be highly concentrated. It must also be reapplied whenever the smell is no longer noticeable upon first entering the treated area. More »

According to a study conducted by Kansas State University in 2002, ultrasonic devices repel some insects and rats and may interfere with mating. The results of the study were mixed and conclude the devices work better on... More » Science

Rodent repellents of various types can be purchased from established online retailers, as well as from leading brick-and-mortar retail chains in the United States. Rodents such as mice and rats can enter and infest a hom... More » Home & Garden Pest Control

To make homemade gopher repellent, mix castor oil with liquid dish detergent and spray your property with the mixture. Applying the mixture in or around the gophers' tunnels is also an effective way to remove the pests. ... More » Home & Garden Pest Control Furry Pests

Ammonia acts as a natural raccoon repellent, according to HowStuffWorks. Its strong smell aids in warding off raccoons that may try to invade homes and garbage cans. Rags soaked in ammonia can be placed wherever raccoons... More » Home & Garden Pest Control Furry Pests

Cayenne pepper is an effective natural chipmunk repellent, according to Better Homes and Gardens. The strong scent of the spice repels the chipmunks, keeping them away from bulbs and other food sources when sprinkled ove... More » Home & Garden Pest Control Furry Pests

Coyote urine and a commercial product called Raccoon Eviction Fluid are often used to repel raccoons. Both products can be found in home and garden retail stores. Cayenne pepper, black pepper and garlic are also used to ... More »