Graziers make daily decisions with adaptive grazing systems

SPRINGFIEILD, Ill. — Disruption is the key to adaptive grazing systems.

“If you graze the same way every time, every year, by starting in the same paddock and finishing in the same paddock, the system is going to stagnate,” said Brian Dougherty, consultant with Understanding Ag.

“You need to alter the densities, the time of year you graze, the order you graze, the grazing heights and rest periods,” said Dougherty during a presentation at the 2025 Grazing Conference, Maximizing Every Acre with Managed Grazing, hosted by the Illinois Grazing Lands Coalition.

“You don’t have to pick just one of these changes — do a different one next year, mix things up and I think you’ll be pleasantly surprised at the results you get,” the consultant said.

“Grazing management is a tool to use to our advantage to accomplish goals,” he said. “We’re trying to mimic what happens with historically large herds — they were constantly on the go and they weren’t stopping in one place, so that’s short grazing periods, lots of trample and long rest periods.”

In general, Dougherty said, land in Illinois is a little more forgiving and it can tolerate more frequent grazing and shorter rest periods.

“In Illinois, you have some of the best soils and climate almost in the world to graze and we should be taking advantage of that,” he said. “It is very non-brittle here with the humid environment, so you can make a lot of mistakes and it will recover and come back.”

But in a brittle environment in the western United States, Dougherty said, it can be a catastrophe if cattlemen don’t manage the grazing correctly.

“Cattle are an integral part of the ecosystem if they’re managed properly,” he said.

Adaptive grazing fixes broken ecosystem processes, Dougherty said.

“Plants are pumping carbon into the soil and working synergistically with biology to build the aggregates,” he said. “I want to see soil sticking to the roots, that tells me the plant is functioning the way it should and creating glues that hold the aggregates together.”

Mycorrhizal fungi are the glues that build aggregates, Dougherty said.

“A lot of soils are very low, if not completely devoid, of mycorrhizal fungi and that means your soils are broken and the system is not working,” he said.

Root exudates also are involved with building aggregates.

“Plants pump carbon out through the root system to feed the biology,” the consultant said. “Plants need a diversity of environments in the soil including water, lots of pore spaces and both aerobic and anaerobic pockets.”

There are a lot of living organisms in the soil that can fix nitrogen, Dougherty said.

“And a lot of them are actually anaerobic, so if you have anaerobic pockets, some air here and some water there, when the root grows through that, it has everything it needs,” he said.

The key is that the process is constant.

“If you don’t have enough residue cycling and breaking down to provide carbon for the microbes, they’re going to start eating the glue that holds your soil together and it’s going to completely collapse,” Dougherty said.

“That’s what we see every year with all these bare fields. The soil is collapsing because there’s nothing feeding the biology.”

Worms in the soil are important because they create the macropores in the soil.

“Macropores are the big pores we can actually see,” Dougherty said. “They are only about 1% of all the space in the soil, but they account for 70% of the water infiltration so if we want water in the soil we’ve got to have macropores and worms.”

Aggregates allow the soil to breathe and infiltrate water.

“I think air is the No. 1 limiting factor on most farms,” Dougherty said. “Photosynthesis is taking carbon dioxide and water to make sugar and then plants pump that into the soil to feed the biology.”

The biology in the soil takes in oxygen and gives off carbon dioxide.

“If I want more photosynthesis, I need more carbon dioxide and water,” Dougherty said. “I get more water by building aggregates and I get more carbon dioxide by keeping the ground covered and the biology breathes out the carbon dioxide right back to the plant.”

The stomata on the bottom sides of leaves captures carbon dioxide.

“It’s there because the plants are designed to catch carbon dioxide out of the soil and not the carbon dioxide floating around in the air,” the consultant said. “It will do that, but only if the plants run short.”

If a pasture does not have good ground cover, Dougherty said, the soil temperatures can reach 130 to 140 degrees.

“Right at about 105 degrees, you start cooking your biology and the proteins and enzymes will start to degrade,” he said. “You’re cooking the life right out of the soil, so you have to keep it covered.”

Adaptive grazing research shows increasing the number of paddocks has a positive impact.

“Ten to 15 paddocks are a minimum and you really want more like 20 to 25 paddocks in order to get the rest periods you want,” the consultant said. “And you can do that with temporary fencing.”

Probably the most important aspect is constant observation and adaptation, Dougherty said.

“You will be making decisions every day on the fly,” he said. “It’s not a rigid system or routine practice, it’s adaptive versus a prescriptive type of grazing system.”