Is your puppy turning your yard into a minefield? If you answered yes, discovering the reason why your puppy is digging up your lawn will help you deal most appropriately with his behavior.
Why puppies dig:
Fun: Puppies dig because they have a lot of energy, and digging helps them expend some of it. If your puppy is digging to have fun and expend energy, you can discourage his digging by providing other outlets for him. Keep your puppy busy and active by playing games with him, and taking him for walks. Keeping your puppy active and occupied will help use the energy he formerly used for digging.
Nesting: A hole in the ground may provide a comfortable nest for your puppy. On a hot day the cold soil may also provide relief from the heat. Help your puppy keep cool by providing fresh water for him to drink, a shady area for him to retreat to, and maybe even a small plastic wading pool for him to cool off in.
Escape: Is your puppy digging because he has discovered that it provides an escape from the yard? Ensure that your fence is in good shape so as not to make the escape easier. If your neighbors welcome your puppy with treats ask them to stop. The treats may be encouraging your puppy to visit them, perhaps by digging an escape route under your fence! Supervision is the best prevention.
Fright: Is your puppy digging because he is frightened at being alone? Let your puppy know that you are not abandoning him when he is left alone for a short time. Leave your puppy for a few minutes, and then return with a treat for him. Do this again, letting the interval you are out of sight last a little longer. After doing this a few times, your puppy will understand that just because you are out of sight doesn't mean you have abandoned him. Of course, your puppy should never be left unsupervised for long periods.