Over the summer, a black shiny substance has appeared in one corner of our lawn. I am not sure what it is. The grass remains fine and it seems to live at the base, on the thatch/soil. It is really shiny but not wet or slimy.
I have twice used a hose to blast it away, but it always returns. I suspect I am never getting all of it and thus it just grows again.
I am really concerned as the pacth is slowly growing.
Anyone know what this is and whether treatable ? I am thinking of either putting in a small trench to try and save the rest of the lawn or perhaps hammer in some wooden shuttering to form a barrier.
If not treatable, assume my only choice is to remove the affected area and re-turf ? Hopefully this is surface infection only, not in the ground (i.e. would come back through new grass).
Any help or ideas welcome.