The news of the antibiotic properties discovered in a mushroom which grows on horse dung reminded Stalker of the old remedies used by the grandparents.
In one instance, pre-antibiotics, the cure for a seriously septic finger was to wrap the offending digit in a poultice of horse manure. The outcome which resulted in a rapidly cured hand was always deemed to be amazing, if not miraculous.
Perhaps here is the reason why it worked, the newly discovered agent called copsin in the mushroom that kills bacteria.
As Grandpa Joe used to maintain, there was always a cure in the fields or the hedgerows for any ailment that afflicted you! Maybe he was right.