A tale of two thresholds: Mistakes and serendipity in a desert grassland

Semiarid grasslands have crossed thresholds to shrub-dominated states due to heavy grazing episodes and their after-effects. Extreme weather events and restoration actions can trigger varying degrees of grass recovery. While we understand these thresholds in biophysical terms, we have scarcely explored their ultimate societal causes. We will reconstruct thought processes underpinning threshold events on the Jornada Experimental Range, including some recent first-hand experiences with managing them. Over a century, we have both over- and underestimated resilience. Given the large management extents and heterogeneity of drylands, appropriate mental models are among the most important tools we have to manage thresholds.