How rude!

Sometimes you get a surprise when you peer at an harmless tree and are met with a cluster of little extruded tongues. Taphrina aldi is back!

It's a fungal pathogen that infects the unripe green cones of the alder tree and stimulates these curly growths (languets, meaning tongue-like) to emerge. The galls are not the fungus (which is invisible to the naked eye), simply its effect.

They have a lubricious appearance especially as they gradually turn pink and then red before turning brown and falling off.  I think of them as goblins' tongues but until recent years the fungus was too rare in the UK for the galls to acquire a popular name.