I grew three batches of parsnip last season, a growout of 50 plants of Kral original seed, a patch of Halblange Weisse F1X mass cross, and a patch of Kral F1X mass cross. Eaxch of these was probably only 1.5 metres square, so relatively low numbers of parents. These patches were allowed to cross at will, the two mass cross beds were next to each other, and relatively synchronised in flowering starting in spring and still going on this autumn,, but the original Kral bed was about 3 metres away, and had a very extended flowering period, right through last winter, spring and summer.
Since the Kral originals were grown from plugs and transplanted, I didn't assess the roots since the transplanting was likely to have distorted the shapes.
And I didn't assess the mass cross roots before harvesting the seed - there just weren't enough plants to risk digging them up.
But after harvesting most of the seed from the mass crosses over the last month or two, I pulled the plants up.
Here is the result, Halblange F1X on the left, Kral F1X on the right. Garden fork for scale.