Click the image to enlarge.
A source of sneezes;
allergies growing on treeses.
The dictionary tells me these are called catkins.
It’s been a while since I saw Monty Python’s “How to Recognise Different Types of Trees From Quite a Long Way Away”, and anyway this one is quite close up, so I can’t be sure, but I’m hazarding a wild guess that this particular tree may or may not be a birch.
Edit: It has been kindly pointed out to me that this is not birch, meaning it has to may or may not be something else.
Fortunately for myself I’m not allergic, so no photographers were harmed during the taking of this picture.
Taken on 01-Apr-2019.