Hello all

In (what I loosely describe as) the lawn in our orchard
a lot of approx. golf-ball-sized holes have appeared
in little clusters.

There are no mounds of earth;
so I assume these are not being made by moles or voles.
Can anyone suggest what creatures are responsible ?

These creatures don't appear to be damaging the younger trees.
However, they did almost damage me
when one foot of the ladder sank into such a hole
and down I came.

Best regards from Ray