This hole has appeared in the soil in one of my buried lattice pots during the last week. Is the hole the result of a 'friend' like a green woodpecker digging for grubs or a 'foe' like a small rodent digging for bulbs/corms? It's in a raised bed inaccessible to medium-sized mammals (like a hedgehog) and, for scale, the sides of the lattice pot are 11cm long.