Had I been advising you in a legal capacity I would have asked how the hives are accessed. If they can be reached without causing damage, say by climbing over a gate, I would have suggested writing to the landowner asking for access to retrieve your property at a set time. If he did not come then to let you in, go get them. If you've not caused any damage no solicitor would suggest to him that he should take action for trespass in such circumstances.
If you would need to cause damage you open yourself up to prosecution for criminal damage, and your only legal route would be to litigate.
So I could not possibly advise that you cause damage, even if it is only to an easily replaceable padlock.
In such a case if I were a private individual so affected, I would write the letter seeking access and if he doesn't appear I would cut that padlock and get my hives, dropping off a padlock of similar quality at his home on my way to my new apiary. Although I would have caused criminal damage, given the letter and the replacement padlock it is unlikely the police would be interested.
But of course, I would never advise you to commit a criminal act like that.