April 2020
I am having this issue too. It seems to be only in the new Pets game pack. There are trash plants growing on the beach, on my back patio, on the docks by the water, etc. And there is no way to remove them in these places.
It's ugly and annoying.
I have all the expansions, game packs and stuff packs.
December 2020
January 2021
I no longer live in Brindleton Bay because of this. I find the continuous presence of pet poo and trash plants puts me off.
Stray pets poo wherever they are. I don't notice it in time. The pet poo becomes a trash plant. That's what causes it for me.
It might also happen when townie pet owners take their pets on a walk: I hope they're good citizens and pick up the poo!
June 2022
I see this in Brindleton Bay as well. I'm currently playing on that huge lot right in the middle of the world, and there are dozens of trash plants on the boardwalks. I get where they're coming from and why they're there, but can they tone it down a little? Tweak the code so that they don't pop up so often? I don't remember it being this much of a problem until somewhat recently.