Thirty years after that day when my grandfather put the stone axhead in my hands, I understood at last why, as I held that stone, my mind had filled with images of tall corn swaying in the wind, images of women dancing as they held the season’s harvest in their hands. Hearing [my friend and teacher] Maurice Dennis tell the story of the coming of corn was the last stroke of the hoe that fit my own mind to the earth my grandfather had given to me. And I knew that as long as my hands had the strength to hold a hoe, I would work that garden where corn had been cared for by my grandparents and by my great grandparents before them. I would listen to that land just as it had once been listened to by other men and women, generations of Abenaki people and Mohawk people whose stories were told in a tongue as old as the soil. Spring would find me preparing the earth for the Corn Maiden, find me fitting the ground of my grandfather’s garden to plant.
I don't understand why the action of "hearing a story" was "the last stroke of the hoe"? And what's the hidden meaning of "the last stroke of the hoe"?