If the young dog has the energy to participate in stupid behavior, it is a work dog that isn't being worked enough. Shift focus from rocks to training. Don't expect much maturity from a large breed dog until they're about 2 yrs of age. It takes them a while to mature in the mind.

The lab needs to be trained 1 hard day, one day of rest. Supervised when out in your back yard. You may have to be stern for weeks or months, but correct the bad behavior every time. Some pups are hard headed. Obviously this one is more hard headed than your used to. I train pups non stop. One the the hardest headed working breeds: Alaskan Malamutes.

When the pups arent getting training, the bad behavior around here is digging holes that are 4-6 ft deep holes and getting tangled under roots.
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