How do you hold on to neighborhood cats out of the backyard?

I have two inside cats, and there is a neighborhood cat that keeps coming into my backyard. My feminine cat goes wild when she sees it and ends up taking out her aggression on my sweet manly cat. I am so FRUSTRATED with this cat. I live in a townhome association, so I am not certain who owns this cat, any suggestions on how to keep this cat OUT of my backyard?
a dog
Why don't you just get your womanly cat spayed so she doesn't have that reaction?
Answers:    You may want to try something called Liquid Fence. It's an animal repellent. Depending on what version you buy, it can hold past its sell-by date dogs, cats, deer, even rabbits and raccoons. You can buy it in liquid concentrate form to where you hold to mix it up yourself, or you can get it in ready to use spray - it's in position to use the moment you're home and out of the car.

It can be a little on the pricy side, but a company I used to work for call Southern States sold it and our customers swore by it. You should be able to get it at any Wall Mart; perhaps even a hardware store or nurture store.

Once you have found some, look at the ingredients. Then you should be able to come up with your own recipe to hold the invading kitty at bay.
get a .22 rifle near birdshot and blow the thing to bits
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