I know this will sound surprising to some, but most worms are helpful. This isn't one of those. It's a nasty invasive worm that has been spotted in Missouri and if you try to cut it, you're only making it stronger.
I am normally a live and let live type of person. However, in this case I'll make an exception. There is an evil invasive worm in Missouri and if you see it, you really should kill it immediately and that's not an overreaction.
The word is that Missourians could see the return of an awful invasive worm this year. It looks like a combination of a hammerhead shark and a worm and it's really bad news.