That's a very healthy looking Palmer amaranth.

You might want to pull that plant before the seed fully develops and you have it all over your garden.

OH DEAR!

Thanks so much as I was scratching my head. I walked right out and cut that thing down immediately. One mini miracle of being a first timer is that I actually FOUND the red pepper plant that was supposed to be in the planter under that thing.

I will have to keep an eye on the pot because I could not pull the roots without disturbing the real plant I wanted.

Any guess whether this thing will be a problem in my "hot" compost pile?

It shouldn't be a problem in a hot compost pile. It wouldn't even be a problem in a cold compost unless the seeds were fully mature.

Rodney

Thanks, theforgottenone1013.

I cut it up and placed in the compost pile.