If you're going to live trap, be sure to release them at least 3-4 miles away, preferably across a major roadway or river. I have a buddy who live traps professionally - when he catches squirrels, raccoon's etcetera in a particular area and then releases them in another - he'll distribute his flyers in the area where he just released.
There are several effective ways to rid your yard and garden of squirrels.
Feeding squirrels separately, away from the garden is one commonly suggested technique. Like catch and release, it works for a while, but will attract not only more squirrels, but other varmints from the rodent realm as well.
If squirrels and other mammalian pests are overrunning your property it's because they're finding food there.
You don't want a food source around - rake up nuts and berries from the ground - this includes acorns, and dispose of them. Make other food sources inaccessible, such as garbage pails they could eat from, be sure to use a sealable lid.
Naturally you can't dispose of your garden crops but you can disguise them somewhat. Squirrels, like most animals rely more on their sense of smell than we humans do. The scent of the mothballs will deter squirrels, rabbits, raccoons etc.. mothballs should be wrapped tightly in a porous sock and placed strategically in fruit trees and the garden area.
You'll have to continuously replenish mothballs as they will disintegrate with each subsequent rain.
The most obvious deterrent to squirrels are dogs, who love to chase them. Some cats will also, but primarily dogs. Motion-activated sprinklers do the trick , but only on a portion of the yard where the motion detector and sprinkler is aimed.
Commercial products on the market are generally made from natural ingredients, such as pepper which will repel squirrels. These repellents can be added directly to bird feeders, as it won't bother the Birds. Other products are made with predatory animal urine, and are meant to be sprayed in strategic areas to scare squirrels and other pests away. Moth balls, Hot peppers, peppermint, cinnamon and Castor oil all serve as squirrel repellents and home made concoctions can work just as well as commercial ones.
Apply this pepper spray strategically where you want to deter squirrels. You'll need to shake it each time as the oil will separate when left to sit.
Common household Olive or Vegetable oil -Applying it to metallic surfaces such as fences, railings, poles and bird feeders where squirrels are known to frequent and watch the show as they try to climb or perch on them and slide off. Harder to reach places - use a spray can of Pam . The squirrels shant be able to scurry along these surfaces and the oils are not water soluble so won't wash away readily. Reapply the oil periodically and the squirrels will stop trolling your yard.
The smell of Moth Balls repels many critters - squirrels are no exception. In locations such as attics and basements they will last for years. In outdoor locations , they will disintegrate with the rain and need to be frequiently replaced.
Ammonia will also work, but should be diluted with water.