As I was walking through the park-like surroundings of All Saints Church in Penarth today, I noticed these curiosities growing amongst ivy under a couple of the trees. As the trees were different but they had ivy in common, I assume these are Ivy broomrape. Their scientific name is Orobanche hederae which, according to Wikipedia, translates as follows: ‘Orobanche is derived from Greek, and means ‘legume strangler’ … The name hederae means ‘of ivy’, in reference to its host plant, Hedera.’
All the broomrapes, the Orobanchaceae, are parasitic plants: they are unable to manufacture their own chlorophyll so cannot exist without tapping in to the roots of their host plants for nutrients. In this case the host is ivy but there are also broomrapes that parasitize trees like hazel and elm and plants like yarrow, greater knapweed and various thistles.