Found an awesome pile of coy-wolf scat, fresh and hairy with raccoon:
If you're intrigued by coy-wolves and their prodigious droppings: A little more info, and some of my photos, of who laid that great turd here
Initially, I was thrown off by the large splash pattern of the feathers, which suggested a mammalian predator such as a bobcat. They were scattered for about 12' around in a big circle.
The feathers were also quite bedraggled and wet, and had been torn out in great clumps. All suggestive of a mammalian predator. But it has been very dewy, so maybe it wasn't saliva that made them so disheveled.
Aha! Stuck to a little relay box on the pole are two vital clues: the barred owl's stomach contents (a partially digested katydid), and a clump of plucked barred owl feathers.