More of the same is not a good thing when it comes to pastures.
“When you have a monoculture above the ground, you have a monoculture below the ground,” said grazing consultant Allen Williams.
“In most monoculture situations, you have mined out many of the available minerals within the first two or three strata of soil.”
But below those monoculture root depths are a lot of minerals not being used by the plants, Williams told attendees at the Western Canada Conference on Soil Health last month.
In diverse pastures, plants can grab the deeper minerals and when animals graze these plants, they remineralize the top strata of the soil, said Williams, a farmer and president of Livestock Management Consultants.
When combined with bale grazing, winter stockpile grazing, and high-density grazing, the result is more organic matter and soil microbes.
“In the trials we’ve done, we’ve built soil organic matter at about one per cent annually,” he said. “It is very easily achievable with the right management practices.”
Diverse forages also improve animal health. Williams pointed to studies by Utah State professor, Fred Provenza, that found different forages have different nutrient and chemical compositions.
Researchers have also found that livestock like a varied diet. When given the opportunity, they will select and browse up to 50 or more plants in a single day. And those animals were healthier, performed better, and had fewer parasites.
Different plant species also emit chemicals that can ward off pest insects, so one plant growing beside another can prevent insect predation on a neighbouring plant.
“Diversity and complexity allows us to be able to significantly reduce our reliance on chemicals such as pesticides and herbicides,” said Williams.
Everything a producer does in agriculture has multiple effects, he said.
“Whether for good or for bad, every decision we make has a compound effect on our land, never a singular effect. We need to remember what else we are impacting when we make poor management decisions.”
For example, the majority of soil microbes exists in the root zone of plants, and if plants are overgrazed, the roots will not grow as quickly.
But changing your practices can bring relatively quick results.
Five years ago, Williams bought a farm that had been very poorly managed. Since then he’d increased soil organic matter; reduced weed populations; increased forage species and water infiltration; and seen a resurgence in earthworms, pollinators, soil insects and wildlife populations. And soil carbon levels were higher than his neighbours — one of whom rotated his cattle every two weeks and the other allowed his cattle to roam all over the entire farm.
Williams compared his grazing practices to the workout routines of high-performance athletes.
“For elite athletes to perform at a high level on a consistent basis, they do not do the same exercise routine every day because they would plateau. They start by resting. The human body, to continue making progress and performing athletically, must have disruptions. Nature is the same.”
Change it up
Williams practises disruption on his farm by changing up his stocking densities and using different rest periods.
“Our natural tendency is to settle into a routine and have a recipe,” he said. “We need to fight that tendency. Don’t move through your farm or ranch in the same rotation every time.
“Altering the patterns of movement through your farm or ranch is another way to be disruptive.”
Williams also alternates the grazing heights of his forages, but makes sure that if they are being cropped shorter, there is plenty of soil moisture for regrowth. Producers can also alternate the order of grazing species if they practise multi-species grazing.
“There are a whole host of ways we can be disruptive. But being disruptive is important because you will keep your soil and plants guessing and keeping them from plateauing and becoming stagnant. One of the reasons we have explored this is because we had people coming to us after doing high-stock density grazing for three or four years, but things weren’t changing rapidly anymore. They’d settled into a system or recipe, and when we started introducing disruption, we moved past it.”
The right animals can make grazing more productive, he added.
Bulls should have a modern frame with thick, easy fleshing, depth in the flank and good capacity in the midsection. When viewed from behind, the widest part of the body should be the lower third of the midriff. Cows need to be sound in the feet, legs, eyes, and udders, and also deep in the heart, girth and flank. They should also have good capacity in the midsection and have a wide lower third midriff.
For optimal animal performance, it’s good to graze forages that are slightly beyond midstage maturity, he said.