Ailanthus is a native evergreen tree in Hong Kong, with leaves clustered at the tips of its branches, resembling an umbrella. This species is quite rare in the wild, and has been listed in Rare and Precious Plants of Hong Kong, and assessed as "Near Threatened" within China. Its scientific name Ailanthus fordii was taken from the collector of the type specimen, Charles Ford — who was also the founder of the Hong Kong Herbarium.

Thanks to the advancement of legal protection and ex-situ conservation efforts, Ailanthus is now very common in Hong Kong, and is widely used in urban and garden greening. It is said that as male trees emit an unpleasant odour when blooming, generally only female trees are planted for urban greening.