This Desert Tree Fed Civilizations for 4,000 Years – Then We Called It a Weed For four thousand years, mesquite trees fed entire civilizations across the American Southwest. Its golden pods provided natural sweetness, complete protein, and life-sustaining nutrition in places where nothing else could grow. Then, in less than a century, it was nearly erased – burned, poisoned, and called a weed. But beneath the soil, the roots waited. And now, as modern droughts intensify and sugar-related illness spreads, scientists are rediscovering what indigenous peoples never forgot: mesquite may be the most resilient food crop on Earth.