Very nice Uri.
It's kind of funny. The NE corner of Tennessee, is near the southernmost end of the range for regina. The elevations are higher and its cooler and wetter than it is here in Middle TN. In middle TN we still get some snow in the winter and extended periods below 0C. But in the summer we get around 100 fairly frequently. We average about 36 to 48" of rain here too.
We are right in range for Cyp. pubescens in middle TN, and in east TN Cyp. acule can be pretty common. But to come across the big stands of Cyp regina you need to go much farther north to States like Wisconsin and Minnesota where they get buried in snow all winter.