Brown paper bag filled with an empty milk jug. They think it's a hornets nest and they move on. I put em out every year.It does look like some kind of borer. From your pic it appears this is outdoors, so I'd suggest looking straight up over that little pile. Look for a fresh hole in any wood overhead, if there is any. Then I'd check everything carefully. In my area we have carpenter bees that bore 1/4" - 1/2" holes in decks, posts, whatever they can find.
No offense intended ,but I believe you are looking at some of the later pictures in this thread .The original post does not have a borer hole.To go cutting at random on the stalk is crazy talk .Hay, @buckaclark, I see you think that's funny. Maybe it is. But it's no different than sticking a pencil through the main. Some people do that. A little work on the plant is better than just kissing it off and from what I've read about this plant I would try to save it. If the plant is healthy enough it should heal. (Maybe ?)
I thought I read the whole thing, must have missed something. And, I could have worded it a little differently.No offense intended ,but I believe you are looking at some of the later pictures in this thread .The original post does not have a borer hole.To go cutting at random on the stalk is crazy talk .