Sample processing impacts on single wet sieve aggregate stability analysis

Soil aggregate stability is widely considered an indicator of soil health. However, there is a lack of test procedure standardization for this soil property. Presently, air‐drying and manual grinding are commonly used in preparing samples for testing, which are time‐consuming and labor intensive. This study evaluated oven‐drying (65 °C) aggregates and processing by either disk or flail mechanical grinders as a way to improve efficiency of conducting aggregate stability analysis as compared with air drying and manual grinding. Surface soil samples were collected from forest, grassland, no‐till, and cultivated areas across 22 fields in Oklahoma with textures ranging from sandy loam to clay loam. The stable fractions of oven‐dried samples were highly correlated to the results of the analysis that used air‐drying. The stable fractions of mechanically ground samples were also highly correlated with manually ground samples. Oven‐drying in combination with either of the grinding methods is a suitable way of improving the efficiency of soil aggregate stability analysis. Core Ideas Oven‐drying provided mean weight diameter of soil aggregates similar to air‐drying for all grinding methods. Manual, disk, and flail grinding methods produced comparable mean weight diameter values for soil aggregates. Oven‐drying and mechanical grinding provide suitable, efficient preparation of soil samples for aggregate stability analysis.