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.

Soil Health Conference Registration Open!

The 2025 Soil Health Conference will be held Jan. 15-16 at the Ramkota Hotel and Event Center in Watertown, a spacious venue which will allow for a full day and a half of speaker sessions, awards, producer panels, and time to engage with sponsors. This event will feature many speakers including Keith Berns, Nebraska no-till farmer, ag educator, and co-owner of Green Cover Seed; Paul Jasa, noted Extension egineer at University of Nebraska-Lincoln; Dr. Jon Lundgren, Ecdysis Foundation executive director and CEO of Blue Dasher Farm; and Joe Breker, an award-winning North Dakota producer who has been using regenerative agriculture practices for over 40 years!

News & Events

Study finds soybean yields resilient following late rye termination

Study finds soybean yields resilient following late rye termination

By Janelle Atyeo For South Dakota Soil Health Coalition PIERRE, SD – A cover crop of quick growing cereal rye can keep the soil in place over winter’s brown and blowing days. Its long roots soak up excess spring rains, and its straw helps block weeds. The more...

Restaurateur promotes local food for community security

Restaurateur promotes local food for community security

By Stan Wise PIERRE, SD – When Sioux Falls restaurateur Tim Meagher purchases local food, he doesn’t do it because it’s trendy. For him, it’s about securing a future for his business and the community. “If somebody else has control of our food system – if you were a...