Answer: What you have is a northern garter snake. These are generally considered beneficial in the garden because they feed on snails and beetles and other insect pests. They are usually 18-24 inches but can grow up to 48 inches long. There are no safe, effective snake repellents capable of keeping snakes away from yards or pools. However, if snakes are inhabiting small, confined areas - such as that crevice behind the front steps - a few tablespoons of naphthalene ("moth balls") may temporarily drive them out so that the entrance can be sealed.
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