Crazy observation - I know. I was hiking through the Denison Biological Preserve on October 26th, 2011 and my jaw dropped when I found a jack-in-the-pulpit in full bloom on a ridge. I specifically took a photograph showing the fall colors in the background and on the forest floor as further proof. Honestly I would have been skeptical of it myself had I not seen it first-hand.
A variant of Great Blue Lobelia (L. siphilitica) that has white flowers. This was found growing in a ditch amongst dozens of normal L. siphilitica.