Reclycling at a new level !

I noticed when I was getting into the car during the week that the teazels had wee growths on them but was on a mission so kept going ... today I investigated the phenomenon ...and there were a number of dried teazel heads growing little plants, I have never seen this before and I consulted a keen nature husband and wife who have also never seen this ..... a theory is that is could be birds have come and left other seed in the teazel head ? but I am thinking perhaps it is actual teazel seeds that have not been nabbed that have germinated and grown in situ ! soooo am going to plant a couple of these heads and see what the outcome is .... anyone else noticed this unusual phenomenon .....