Is this a weed?
Hello-- If you have time to deal with this question, here it is: I have several of these plants growing in various gardens at my house. I think this is a weed, but I'm not entirely sure. I couldn't ID it from the weeds listed on this website. The plants are about 3.5-4 feet tall. They grow straight up with a main stem and then grow smaller stems at the bottom of the plant that don't get as high as the main stem. I've attached photos. Many thanks for your help and for this wonderful service.
Looks like American burnweed. Read what we have on our webpage, though that photo is a much more mature plant: https://extension.umd.edu/hgic/american-burnweed You can see photos more similar to yours if you search online and look at Images.
You'll want to pull them before they get any bigger.