There are many ways to keep squirrels out of a yard, such as getting a dog or sprinkling cayenne pepper around the yard, but what keeps squirrels away in some areas may not work in others. There are humane methods of removal, such as trapping the squirrel and relocating him several miles away, and there are more lethal methods that involve trapping, shooting or burrow fumigation.
Burrows can also be flooded as another humane method of removal. This destroys the squirrels home and gives him less of a reason to return to the yard. Predator urine is another squirrel repellent that works similarly to cayenne pepper; however, both only repel the animals for so long, and they might become used to it over time.
Depending on the area, it may be legal to hunt certain squirrels, but it is important to check state hunting and fishing laws. Poison is another possible method of removal, although there are no poisons marketed solely to kill squirrels, as of 2015. Some sources state that the best poisons to use are anticoagulants or acute toxin bait traps, such as Gardening Know How and PestKill.org, but both heed a warning. Poison should be handled by a professional in most cases, and it is considered inhumane by many because it causes a slow, painful death.