We are developing a soil physical health testing laboratory to offer rapid, scientifically meaningful, and agronomically useful tests, inexpensively performed for public service. This study assessed properties for their usefulness as soil health indicators: aggregate stability, saturated hydraulic conductivity, several pore size parameters (pores above field capacity (> -10kPa), available water capacity (-1500 to -10kPa), and effective porosity (> -1500kPa)), penetration resistance at -10kPa, and bulk density. Controlled long-term soil management experiments at Willsboro, Chazy and Aurora, NY were used to 1) evaluate the utility and sensitivity to management of each test and 2) determine whether seasonal variability in indicator values necessitates specifying the timing of sampling. Several indicators showed significant differences and trends between long-term plow-till vs. no-till systems, between cover-cropping regimes, and sporadically between soils under maize harvested for grain vs. silage. The aggregate stability test (WSA), using 0.25 – 2 mm aggregates, showed treatment differences most consistently and significantly. WSA values were higher by 16 to 40% in no-till than in plow-till systems, and by 5 to 32% in maize-after-grass than in continuous maize rotations, depending on soil type and sampling date. Bulk density, available water capacity and pores above field capacity also showed usefulness as indicators. Seasonal variability of indicator values was significant, and thus we conclude that timing of sampling must be specified. We encourage efforts by scientists, farmers, consultants and extension agents alike to further explore the practicality of soil health testing for public service.
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