You could try a couple things. If they are chewing to keep up dental health, you can try spraying with a deterrent like bitter apple or hot pepper spray. If it's chewing due to calcium issues, putting out something like an antler or bone meant for dogs can help distract them.

Try moving the garbage bins do they are not so close to fence or leave it some nuts (food) maybe its hungry?

@beesneeds I don't suppose there is a good commercial product that would mix the bitter apple or pepper into something that would stick to the vertical wood?

How would I test for calcium? Just set out some dry bone onto a plate and see if that gets eaten? Not sure I want to be feeding squirrels long-term....

@Momof5x Unfortunately, there is nowhere else to put the huge number of cans I have. They are all 96-gallon cans loaded with soil materials for gardening.

Ah ok - other options that will not harm the squirrel is adding soft meshing on the top of fence, an owl decoy that moves a little with the wind or anything similar, wind chimes, water spray in garden that sprays when sensing movements- i even know someone who just tied a plastic bag on the fence and the wind would move it and scare them off.

Deterrent sprays stick to vertical and horozontal surfaces. They don't get mixed with anything, you just follow the instructions on the bottle. Reapply as necessary.

You could maybe get a dead animal tested for calcium. Or if you area is seeing a squirrel gestation season, it could be that- mother squirrels seem to like/need it.

@klem1 Cute :)