Fungal growth on a wild rose?

Does anyone know what this growth might be?

It vaguely reminds me of the fungal disease on trees that makes the tree to grow a round thicket of twigs, but this is on a wild rose and actually grows not only on the stem, but on the leaves.



Never seen this before!

Thanks

 

Looks like Robin's pincushion, if it's on a rose or related species.

 

It's caused by a gall wasp and is harmless.

 

Robin's pincushion it is, thanks very much! Always nice to learn something new

 

I think the one you were originally thinking of (tight bunches of twigs/leaves) is Witches' broom' @Selleri

 

We call it "wind's nest" in Finnish- quite a good name too.