Answer: Slugs and snails can cause the kind of damage you describe. They usually feed at night, so they're difficult to catch in the act, but you might try going out late at night or early in the morning to check on the fruit. For control, handpick and destroy the pests as you find them. Copper foil barriers can be placed around the trunk of your tree to keep snails from slithering up and munching on your lemons.
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