Chemical Properties

Reactive Carbon

Slaking is the breakdown of large, air-dry soil aggregates (>2-5 mm) into smaller sized microaggregates (<0.25 mm) when they are suddenly immersed in water. Slaking occurs when aggregates are not strong enough to withstand internal stresses caused by rapid water uptake. Internal stresses result from differential swelling of clay particles, trapped and escaping air in soil pores, rapid release of heat during wetting, and the mechanical action of moving water.

Soil Electrical Conductivity

Soil electrical conductivity (EC) measures the ability of soil water to carry electrical current. Electrical conductivity is an electrolytic process that takes place principally through water-filled pores. Cations (Ca2+, Mg2+, K+, Na+, and NH4 +) and anions (SO4 2-, Cl-, NO3 -, and HCO3 -) from salts dissolved in soil water carry electrical charges and conduct the electrical current.

Soil Nitrate

Nitrate (NO3 -) is a form of inorganic nitrogen (N) naturally occurring in soils. Sources of soil NO3 – include decomposing plant residues and animal manure/compost, chemical fertilizers, exudates from living plants, rainfall, and lightning.

Soil pH

Soil pH generally refers to the degree of soil acidity or alkalinity. Chemically, it is defined as the log10 hydrogen ions (H+) in the soil solution. The pH scale ranges from 0 to 14; a pH of 7 is considered neutral. If pH values are greater than 7, the solution is considered basic or alkaline; if they are below 7, the solution is acidic.

A photo of several people standing in a field of cover crops that are about shoulder high.

Registration Open for Two Soil Health Schools!

The 2025 West River Soil Health School will be held June 25-26 in Caputa, SD, and the 2025 Soil Health School will be held September 3-5 in Huron, SD. Each of these two schools will feature outstanding instructors consisting of industry professionals, researchers, and experienced producers. The days will be split between classroom discussions and field exercises designed to help you improve your land and your profit margins through regenerative agriculture practices. Visit our events page to learn more about these excellent learning opportunities!

News & Events

Virtual fences can make a real difference

Virtual fences can make a real difference

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Regenerative ag can grow the bottom line

Regenerative ag can grow the bottom line

By Stan Wise PIERRE, SD – As regenerative agriculture gains traction as a hot topic, one question dominates the farming community: Does it pay? Simply put, yes, it does. Regenerative ag is an approach to land management that focuses on improving soil health,...

Awards, new board member announced at Soil Health Conference

Awards, new board member announced at Soil Health Conference

PIERRE, SD – The Ninth Annual Soil Health Conference, Jan. 15-16 at the Ramkota Hotel and Event Center in Watertown, SD, saw approximately 500 attendees, including over a hundred students. The South Dakota Soil Health Coalition was thrilled to offer this opportunity...