There were definitely other weeds in the bed but this one really stood out. But anyway, I doubt they would allow it to grow up into a big Rain Tree, would they?
By the way, the combination of yellowish-green Polyscias fruticosa (Family: Araliaceae; common name: Ming Aralia) and purple-leaved Tradescantia pallida (Family: Commelinaceae; common name: Purple Heart, Purple Queen) was quite interesting.
A link on the Purple Heart is provided below:
NB on 2 Sep 10: Just as I expected, the Rain Tree weed was removed.