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Lack of adoption of soil health–promoting practices (SHPPs) leaves soil vulnerable to erosion, exacerbating flooding and contributing to high nutrient and sediment levels in surface waters. To aid in the adoption of SHPPs, changes in soil health need to be measured and related to things that both clearly and directly matter to farmers and stakeholders, yet soil scientists still grapple with which indicators to measure when assessing soil health. Useful indicators of soil health show changes in soil function resulting from changes in soil management, are measurable, and have clear and direct value to their target audience. These “linking indicators” need to be identified in context for successful promotion of SHPPs. We collected data from two focus groups of farmers in the Brazos River Watershed, TX, who had either adopted SHPPs or who had not. Content analysis of focus group transcripts revealed soil health was an important part of a farmer's stewardship ethic. Farmers perceived that water management, organic matter, yield, and biomass were meaningful indicators of soil health that benefited their enterprise. However, using yield and biomass alone has the potential to create a “false positive” for soil health. When farmers chose their management practices, two themes interacted with farmer concerns for soil health: profitability and social interactions. This work provides context and recommended linking indicators for soil scientists to use for communication with farmers. Researchers and policymakers should be aware of these interactions if efforts to promote SHPP adoption are to be successful.

Currently accepted pedotransfer functions show negligible effect of managementinduced changes to soil organic carbon (SOC) on plant available water holding capacity (θ AWHC ), while some studies show the ability to substantially increase θ AWHC through management. The Soil Health Institute's North America Project to Evaluate Soil Health Measurements measured water content at field capacity using intact soil cores across 124 long-term research sites that contained increases in SOC as a result of management treatments such as reduced tillage and cover cropping. Pedotransfer functions were created for volumetric water content at field capacity (θ FC ) and permanent wilting point (θ PWP ). New pedotransfer functions had predictions of θ AWHC that were similarly accurate compared with Saxton and Rawls when tested on samples from the National Soil Characterization database. Further, the new pedotransfer functions showed substantial effects of soil calcareousness and SOC on θ AWHC . For an increase in SOC of 10 g kg -1 (1%) in noncalcareous soils, an average increase in θ AWHC of 3.0 mm 100 mm -1 soil (0.03 m 3 m -3 ) on average across all soil texture classes was found. This SOC related increase in θ AWHC is about double previous estimates. Calcareous soils had an increase in θ AWHC of 1.2 mm 100 mm -1 soil associated with a 10 g kg -1 increase in SOC, across all soil texture classes. New equations can aid in quantifying benefits of soil management practices that increase SOC and can be used to model the effect of changes in management on drought resilience.

Funding: Cargill provided financial and other support for the Soil Health Institute to conduct the economic assessments referenced in this paper, but the outcomes, research and views of this paper are independent of Cargill.

The measurement of aggregate stability is widely used for establishing quantified soil condition ratings. These ratings can inform managers and scientists on effective soil management practices and identify regions where poor soil conditions are jeopardizing the environment and soil productivity. However, many current methods for quantifying soil conditions are complicated and time-consuming, and require specialized equipment, especially the measure of aggregate stability. SLAKES is a smartphone application created by the University of Sydney, Australia, that quantifies aggregate stability through a simple experiment. The experiment requires three pea-sized soil peds, a petri dish of water, and a smartphone running the SLAKES application. The application takes 10 min to produce an on-screen measurement of aggregate stability and a downloadable text file of the ped dissolution over time. SLAKES, along with the Cornell Wet Aggregate Stability Test, was used on seven conventional tillage, seven no-till, and eight perennial grass fields to determine whether the application showed sensitivity to different management practices. All 22 sites were on Vertisols (Typic Haplusterts). The SLAKES results showed higher significant separation of means (p < .0001) between each management type than the Cornell method, which was only able to differentiate between conventional tillage and perennial grass management at a lower significance (p = .06). SLAKES proved to be a legitimate method for quantifying aggregate stability based on slaking. With this simplified aggregate stability measurement method, rating and quantifying soil health is viable for anyone with a portable electronic device and is much less tedious than traditional lab-based methods.

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Core Ideas Time for water to fully drain from cracks and mesopores was 24 to 72 h. In moist, cracked soil, water moved to 60 cm after 2 h. On dry, cracked soil, water moved to >120 cm in <1.5 h. The mesopore infiltration module improved estimation of soil profile water content. At the pedon scale, the mesopore module improved ponding predictions. Water is preferentially conducted away from the soil surface through large cracks formed in shrink–swell soils, which complicates our ability to calculate the partitioning of water into infiltration and runoff. Preferential flow paths affect the hydrology of a landscape but often are not included in hydrology models. The Precision Agricultural‐Landscape Modeling System (PALMS) contains a Mesopore and Matrix (M&M) module that allows preferential flow and was tested on cracking soil at the pedon and small watershed scale for this study. Four irrigation events were conducted on 10‐m by 10‐m plots of a cracking soil, and volumetric water content (VWC) output for PALMS with and without the M&M module was compared with that measured by a neutron moisture meter. Additionally, measurements of VWC on a 4.4‐ha small watershed were compared with PALMS predictions. At both scales, the M&M module simulated water movement down the soil profile more quickly and eliminated unobserved ponding at the pedon scale relative to the PALMS matrix only. Simulations of water content of the soil profile were generally improved when the M&M module was used. Furthermore, PALMS M&M was relatively easy to parameterize using obtainable and physically relevant parameters, rendering it applicable to shrink–swell soils in a variety of systems.