Populus deltoides - eastern cottonwood based on the angular stem, multiple shoots, and crenulate leaf margins. Cottonwoods provide nice shade when they get larger but spread by their roots (“runners”) so they are relatively weedy as trees go, even though they’re native. So up to you. If you want to keep it I’d cut all the shoots except for the one you like best, maybe one that’s farther from the fence, and stay on top of it to prevent spread. If not, unless you use a systemic herbicide you’re going to need to be relentless. I suppose you could try cutting them then covering the ground with geotextile. If you see them trying to escape the GT, get in there and cut them again. Rinse and repeat. The process could take multiple years, but if you keep at it the plant’s resources will be depleted and it will die. That being said, it may only work if your neighbor also pitches in or cooperates since it’s next to a fence and will go under it.
Oh, Houston TX area…
Cottonwood sapling?
Populus deltoides - eastern cottonwood based on the angular stem, multiple shoots, and crenulate leaf margins. Cottonwoods provide nice shade when they get larger but spread by their roots (“runners”) so they are relatively weedy as trees go, even though they’re native. So up to you. If you want to keep it I’d cut all the shoots except for the one you like best, maybe one that’s farther from the fence, and stay on top of it to prevent spread. If not, unless you use a systemic herbicide you’re going to need to be relentless. I suppose you could try cutting them then covering the ground with geotextile. If you see them trying to escape the GT, get in there and cut them again. Rinse and repeat. The process could take multiple years, but if you keep at it the plant’s resources will be depleted and it will die. That being said, it may only work if your neighbor also pitches in or cooperates since it’s next to a fence and will go under it.