Relationship between buffelgrass survival, organic carbon, and soil color in Mexico

T-4464 buffelgrass (Cenchrus ciliaris L.), a perennial bunchgrass from Africa, has been extensively seeded throughout Mexico. After establishment and grazing, T-4464 either persists with time and actively invades surrounding areas (spreads), persists with time but does not increase (persists), or declines with time and all plants die (dies). To help land managers select high-potential seeding sites, we classified 139 seeding sites in three survival regimes : (i) spreads, (ii) persists, and (iii) dies. In previous research, we identified a relationship between plant survival and organic C. This research was designed to identify relationships between organic C and soil color. Single comparisons between organic C and Munsell hue, value, chroma, and reflectance in dry and moist soils were poor predictors of plant survival. To predict buffelgrass survival among the three survival regimes and between spreads and dies, we used discriminant function analyses. In dry soil, a model including value and chroma correctly classified 53% (Wilke's λ = 0.8) of the seeding sites in the three survival regimes, while in moist soils, value and reflectance components correctly classified 61% (Wilke's λ = 0.7) of the seeding sites. A dry soil model including value, chroma, and reflectance correctly classified 81% (Wilke's λ = 0.7) of the seeding sites between spreads and dies, while a moist soil model, including the same components, correctly classified 83% (Wilke's λ = 0.6) of the seeding sites. Survival regime selection with multiple soil color components prior to brush control and sowing will reduce adverse economic and environmental consequences and enhance long-term beef production.