Question about fruit trees and cedar trees

Question about fruit trees and cedar trees

One of my neighbors has a Red Delicious apple tree. She claims that the tree used to make tons of apples nearly every year. Then the landowners across the road let their fence line grow up with cedar trees. Now she claims that the cedar trees are the cause of the apple tree not making more than a couple of apples every year. She says she's had this happen before at other locations - cedar and/or pine trees causing lack of fruit on fruit trees. Has anyone else ever heard of this or had it happen? Personally I've never heard of it before and I'm having a hard time understanding how it could be true. The owner of the cedar trees is a friend of mine. When I mentioned my neighbor's problem to him, he said he'd be happy to remove the cedar trees if I could offer some proof that they are actually the cause of the problem.
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