Noticed this morning.
There has suddenly appeared a white deposit on an area of earth about a
yard square - underneath a silver birch (which may not be relevant).

What on earth can it be?
I don't like to even touch it without knowing.

I scraped a bit up on the tip of a stainless steel table knife - and it
seems to be about a millimetre thick - possibly some kind of fungus -
paste-like when squashed - doesn't cover the whole area - just blotches
of it on the ground.

How can I find out what it is?
Should I be concerned?
Might urgent action be needed?
--
Chris