I do hope you replied to whoever reported it then, Cari and told them to save their over-sensitivity for posts which are really offensive.
I'd say that anyone reporting GandTea for this thread is doing so to be nasty and cause trouble, not because they are genuinely hurt or saddened by a reference to an invasive species being an immigrant. After all, that is EXACTLY what it is. It has moved here, to a strange land, from elsewhere.
The other possibility is that it is someone so tight-arsed and up themselves with defending those who are not being attacked that they see insulting racists under every bed. Another word for that is paranoia!