Answer: What you're seeing may be normal and natural. Pine trees drop needles in the center of the plant after 2-3 years. Their jobs are done and the tree is shedding them because they're no longer needed. Most pines shed nearly one-third of their oldest needles each year. As long as your tree looks otherwise healthy and puts all new growth each year, there is nothing to be concerned about.
Best wishes with your landscape!
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