The prehistoric Hohokam, the ingenious, canal-building farmers, developed “polycropping;” that is planting maize (corn), beans, and squash together. This agrarian trinity became known as “The Three Sisters.” Maize was a natural trellis for the common, climbing, tepary bean. Squash seeds were planted between the maize stalks. Squash grows closely to the ground. With large spiny leaves, evaporation was reduced, pests were reduced, and a natural mulch was created. Maize depletes important nitrogen from the soil; the tepary beans, in addition to being drought resistant, adds nitrogen to the soil.