The land's fruitfulness is the "natural" consequence of covenant faithfulness enacted on both sides, Israel's and God's. A productive land is a gift something like a child to a healthy marriage; in each case, thriving results from and witnesses to long-sustained faithfulness between two partners.
As I went walking I saw a sign there
And on the sign it said "No Trespassing."
But on the other side it didn't say nothing,
That side was made for you and me.
This land is your land, this land is my land
From California to the New York island
From the Redwood forest to the Gulf Stream waters
This land was made for you and me.
My people are few. They resemble the scattering trees of a storm-swept plain...There was a time when our people covered the land as the waves of a wind-ruffled sea cover its shell-paved floor, but that time long since passed away with the greatness of tribes that are now but a mournful memory.
Your own forefathers killed to have and hold the land where you were born, and sought to extinguish the memories and souls of those that were slain. What of those who prayed in the mountains of Appalachia for thousands of years? That to me is an abomination, although it is the way of men.