Open pollination by natural selection and compatibility. This year I discovered something here quite by accident that by the numbers, has to be more than just a coincidence. That is: on stems left to open pollenate, there was a least one fully developed pod with good seed. The number of pods didn't matter, nor did the location on the stem, whether it was five or fifteen, there could be fourteen duds but always one or two big, beautiful pods full of assumable good seed. Upon further observation, if there was more than one pod, the pods would be in line--that is pollination must have occurred pretty much at the same time. And, generally, this seemed most prevalent to an area about 25 X 25 feet, give or take few. Crazy! It's something I've never seen before. But then, I've always snapped off unwanted seed pods in previous years. Could it be I've got a universal pollinator somewhere in there? I should mention, these are Division VI Trumpet/Aurelian seedlings, no more than two sisters alike.
The pictures are not the best, because the fully developed pod is farthest away from the camera lens making it look relatively and comparatively smaller, but you'll get the idea.
