Well, OK, but it's different in the country, isn't it?
It is an absolute myth that living in the country confers greater latitude in the dictum "thou shall keep thy dog constrained to the immediate environs of the pack." Country dogs allowed to run free get shot by hunters or farmers protecting their livestock. They get into fights with other dogs over territory.

They can kill livestock, fight and tassel and get disease from wild animals, and be hit by cars on the highway. They become increasingly aggressive as they eye for larger and larger perimeter boundaries to their territory, and they no longer relate to YOU as the leader of their pack. Also, don't forget that intact animals will breed and add to the overpopulation problem.

This same misconception leads people to dump unwanted dogs "in the countryside." Most such dogs die a painful death, either by slow starvation, injuries from being hit by a car or in a fight with another animal, or they are shot by farmers protecting their livestock. The countryside is not some sort of romantic haven for stray dogs.

When dogs are mad at people, they do all kinds of spiteful things.
First remember that "undesireable behavior" is in the eye of the beholder. To the dog, it's perfectly alright to dig, to bark, to chase after other dogs, etc. This doesn't mean you can't control these behaviors, of course, but it does mean that the dog isn't doing them "to spite you." The dog hasn't a clue that it's not to do these things unless you train it not to. And it has to understand what you want from it!

When dogs start undesirable (to humans) behavior, its best to try to understand the source of this behavior. Often it stems from the frustration of being left alone. Dogs are very social animals. One positive solution is to make sure your dog is properly exercised.

Exercise is a wonderful cure to many behavioral problems and dogs just love it. Do check with your vet for the proper amount of exercise for both the age and breed of any dog. Another solution is obedience training. The point is, your dog needs your attention, whether it is by taking it out on a walk, training it, or both.