If only I had a working camera!
As the ground was unfrozen I attempted to extract a parsnip yesterday.
Nearly did for me it did.
When I eventually got it out I could see why: the diameter at the top was over 6 inches.
Dunno how far down it went - had to break it off to get it put at the 18inch level.
Dunno why but I seem to have a knack for parsnips, rubbish at everything else, but so far parsnips have been good for me.