Do you own a dog? Do you love it? Do you want to keep it safe? One way you can do this is to give it an appropriate place to play outdoors. Many people who live in rural areas assume that they can safely let their animals roam. Those people are wrong. When cyclists and joggers near your property, your dog might instinctually chase them to protect its territory. (Some have hypothesized that the shape and motion of a pedaling cyclist resembles a trotting deer to dogs.) Forget about the safety of the cyclists and joggers for a minute, and think about your dog. When dogs chase us, they more often than not run into the road, putting them at risk of being hit by cars and trucks, not to mention bikes. If you really care about your dogs, give them a fenced-in area to roam. It's safer for them; it's safer for us.
Along these lines, never put your dogs on chains. They are cruel and can cause your dog to hurt itself.