There was a period they were unfleeced - from June until Mid-August, when I thought the CF wasn't supposed to be about...it seems I was mistaken. I pulled all of the carrots from under the part I was harvesting from - they were spring sown so most are a good size anyway, just in the ground to keep them fresh. Just over half were damaged. I'll chop out the bad bits cut them up and freeze them for convenient soup, stew and mince material.
Based on this (and curiosity piqued by Ed's experiment) I took six carrots from under the other two fleeces, all June sown. Two were damaged, coming from the bed I didn't thin ??? ::) Interestingly, (to me anyway) it was the larger carrots that were mostly affected with the few little 'uns mostly escaping. [EDIT - I meant 6 from under EACH of the two fleeces]
I'm far more worried about suitability for storage in sand than I am about appearance. Freezer space isn't that huge.
My June sown will just have to live with it since they are only fingerlings yet. 10% infestation I can live with but I'm hoping the grubs will just remain in the carrot they infected and not travel too far. Anyone know?