Three Sisters plants partition water by rooting at different depths

Evidence

The sisters cooperate above ground with the placement of their leaves, carefully avoiding one another’s space. The same is true below ground. Corn is classified as a monocot, basically an overgrown grass, so its roots are fine and fibrous. With the soil shaken off, they look like a stringy mop head at the end of a cornstalk handle. They don’t go very deep at all; instead they make a shallow network, calling first dibs on incoming rain. After they’ve had their drink, the water descends out of reach of the corn roots. As the water goes deeper, the deep taproots of the bean are poised there to absorb it. The squash finds its share by moving away from the others. Wherever a squash stem touches soil, it can put out a tuft of adventitious roots, collecting water far from the corn and bean roots. They share the soil by the same techniques that they share the light, leaving enough for everyone. — Robin Wall Kimmerer, Braiding Sweetgrass, 463

Categorization

• XREF: Temporal/depth partitioning of the same resource is a niche-partitioning idea that connects to ecology course content on coexistence. — connects to: A Three Sisters garden physically embodies the ethic of reciprocity — Robin Wall Kimmerer, Braiding Sweetgrass: Indigenous Wisdom,…, 459; The Three Sisters companion planting is a feat of indigenous agriculture — Robin Wall Kimmerer, Braiding Sweetgrass: Indigenous Wisdom,…, 451; Root-system depth determines which species survive coastal gales — Vinson Brown, Reading the Woods: Seeing More in…, 163 (+2 more)
• CANDY: Corn’s shallow roots take rain first, then deeper bean taproots and squash adventitious roots claim the rest — a neat water-sharing fact.

Broader Connections

• Root-system depth determines which species survive coastal gales #expands (0.80) — Vinson Brown, Reading the Woods, 163
• Harvesting crowded central clonal plants improves remaining plant growth #expands (0.72) — Robin Wall Kimmerer, Braiding Sweetgrass, 636
• Gap size determines whether lateral branch growth or sapling height growth closes it #expands (0.72) — S. T. A. Pickett and P. S. White, eds., The Ecology of Natural Disturbance and…, 231