Given our recent, seemingly never-ending high temperatures, I’ve been surprised to find fungi flourishing, though they’ve not been the mushroom-shaped life forms you might expect when you read the word fungi. Take today’s fungus, for example. I didn’t immediately realise these very distinctive marks on the leaves of an Elder tree (Sambucus sp.) were caused by a fungus.

These marks are caused by Cercospora depazeoides, and it seems the fungus can be quite destructive. According to the European Forest Pests website, this fungal pathogen leads to ‘premature leaf drop and reduced photosynthesis’. When the spots merge, dominating the leaf surface, they cause defoliation, which can ‘weaken the plant, impacting its growth and fruit production’. Fortunately for those who harvest the berries to make Elderberry cordial, according to iRecord, this fungus has thus far not been recorded in many locations in the UK.