Application of visual soil evaluations in a semiarid region

Abstract

Visual soil evaluations (VSEs) offer land managers a valuable method to efficiently assess soil condition. Scores from quantitative VSEs are often associated with soil properties known to directly influence agroecosystem function, thereby providing useful information to guide management decisions. However, practitioner awareness and adoption of VSEs is limited, particularly in North America. To explore the potential utility of VSEs for practitioner use, a half-day workshop was developed for interested farmers, conservationists, extension educators, and other agriculturalists. The workshop, developed by the USDA-ARS Northern Great Plains Research Laboratory, Mandan, ND USA, provided a brief overview of the Visual Evaluation of Soil Structure (VESS) followed by opportunities to apply the method on five fields with different cropping practices but a common soil type (Typic Haplustoll; USDA). The workshop was held four times between 2018 and 2023 following spring wheat (Triticum aestivum L.) harvest. Workshop attendees were able to discern differences in soil structure among cropping practices using VESS (P ≤ 0.01). Mean attendee VESS scores were 3.8, 2.6, 3.0, 2.4, and 1.1 for spring wheat-fallow, 3-yr, 5-yr, Dynamic, and Dynamic + Manure cropping system treatments, respectively. Attendee VESS scores were significantly associated with the instructor’s VESS scores (r = 0.85), along with measurements of soil organic matter (r = −0.82), soluble C (r = −0.84), C mineralization (r = -0.82), spring wheat grain yield (r = −0.51), and straw yield (r = −0.67). Findings from this study suggest land managers can quickly acquire skills necessary to effectively apply VSEs for assessment of rainfed cropping practices in a semiarid region.