Answer: Squirrels are cute but marauding little critters! The only practical way of preventing them from getting into your tree is to place a squirrel baffle around the trunk of the tree. If there are no nearby trees or power lines from which they could jump into the tree's canopy, you may have a chance.
You can trim all low hanging limbs up to about 4 feet off the ground to prevent the squirrels from jumping into the tree. Then place a piece of metal flashing around the trunk extending outward in a downward cone shape. The metal should extend out about 18" from the trunk. This metal attachment will appear similar to the collar the veterinarian puts around a dog's neck to keep it from scratching its ears.
Place the metal collar about 4 feet off the ground to prevent them from jumping from the ground to the trunk above it.
Good luck with those squirrels and thanks for the question!
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