I'm reading an interesting book, "Dirt: The Erosion Of Civilization."
It discusses how farming practices have changed overtime and many of the techniques adopted have led to soil loss at an unsustainable rate.
The book discusses early Roman agriculture, which was extremely sustainable and soil building.
The technique described is called "cultura promiscua."
A google search didn't turn up much.
Here is the description:
"The earliest Roman farmers planted a multistory canopy of olives, grapes, cereals, and fodder crops referred to as cultura promiscua. Interplanting of understory and overstory crops smothered weeds, saved labor, and prevented erosion by shielding the ground all year. Roots of each crop reached to difference depths and did not compete with each other. Instead, the multicrop system raised soil temperatures and extended the growing season. In the early republic, a Roman family could feed itself working the typical plot of land by hand. (and such labor-intensive farming is best practices on a small scale.) Using an ox and plow saved labor but required twice as much land to feed a family."
Any modern day implementation of this system? Does it go by other names I might be able to find out more about it under?