I read an article you wrote about what causes acorn crops to fail. I have a more specific matter. I moved to Cincinnati from Nebraska in 2015 and was proud to buy a home with a large Shingle Oak in the back yard. Measuring the trunk @6feet and applying a factor I found, it appears that this tree may be over 200 years old. I know white oaks generally produce every 2 years and for the first and third summers we were here the crop was plentiful. Since then we have been getting small, black, berry-like things that smash with a kind of purple smear. And no acorns. I'm thinking these are undeveloped acorns. I'd hate to think the tree is ill or diseased. Any thoughts?