We thin them out around here whenever we get a chance!
If we see one we shoot one!
They really do a lot of damage to the trees in this area!
Other than seeing them while deer hunting or otherwise in the woods, we wait until mid winter and go out on snow and look for a trail and follow them back to their den!
Most times, their den will be either under a boulder or in a hollow tree!
They are real easy to kill! A 22 is all you need, but during deer season we use overkill, be it 30-30, 6mm, 243, 308, 7mm Mag!
BUT, the other guys are correct though! Porcupines are excellent "emergency" food!