In the Wikipedia entry on Celery, the Celeriac wasn't even mentioned, while it is the "de facto celery" of the Europe. If you walk up to a vegetable stand and ask for celery, you're getting a celery root. If the recipe says "add celery" it means "celery root". Celery stalks are less common, only start gaining popularity and generally, while in the US "celery" as a food product means "celery stalks", in Europe it's "celery root".
I added the following paragraph:
In Europe the dominant variety of celery most commonly available in trade is Celeriac (Apium graveolens var. rapaceum) grown for its hypocotyl forming a large bulb (commonly but incorrectly called celery root). The leaves are used as seasoning, and the stalks find only marginal use.
And shortly that entry got a "" mark.
Now how do I provide a citation on something that is just too mundane to create any research? I guess if I linked some statistics that show sales or production of root celery (celeriac) surpassing sales/production of stalk celery (Pascal) it would be satisfactory, but where can I find these?