What do the African Serengeti, the American plains, the Steppes of Mongolia, and the Pampas of Argentina all have in common?
The grasslands covering these regions evolved in the presence of large herbivores. Without large herds of grazing animals, these ecosystems cease to function as they should.
This is a really crazy idea when weighed against what we’ve all heard in the media in regards to the impact animals have on the environment.
Can it be that what hurts grasslands most is too few herbivores? The answer is yes.
Many of our ecosystems appear to be overgrazed, but the reality is that the historic ecosystem functions of grazing land can actually be improved by higher densities of cows and holistic planned grazing. This is the key to farming in nature’s image: Large groups of grazing herbivores kept tightly bunched and continuously moving. In the past, this was accomplished by way of predators constantly patrolling the edges of the herd. At present this is re-created one of two ways.
The Shepherd
Every culture has a different word for this role, that dates back to ancient times. He could be paniolo, cowboy, gaucho, vaquero, or part of historic nomadic tribes like the Bedouins. A human or group of humans make use of the herd animals instinctual flight zone. When we get close to a cow, it moves away from us. We can use this to our advantage in steering the animal towards greener pastures or away from danger. This is still used in semi-arid environments where the cost of fencing immense areas of land is not cost effective.
The Moveable Electric Fence
This is the modern-day version of the shepherd in smaller land areas that also get higher amounts of rainfall. Where you have higher rainfall and thicker grass production, containing the animals for a short while in a small area of plentiful food resources is the common practice. From the cows’ perspective, the electric fence serves the same function as a pack of timber wolves, albeit a bit little less stressful perhaps.
Why are large grazing animals integral to grasslands management? Let me explain how grass works as a carbon pump.
Grass takes in carbon dioxide and releases oxygen. The simplicity and elegance of this seemingly complex reaction — the single process that has helped shape life on earth as we know it — are commonly overlooked.
In the spring, when the grass starts to grow, the cool-season grasses quickly begin to set their seed heads. Grass goes through a life of stages: Infant, teenager, adult, and senior. The stages of life when the grass is cycling the most carbon is when it is a teenager or adult. How do you keep it in that stage for the greatest amount of time? With an animal eating it before it reaches the mature “senior” chapter of life. We don’t want the animal to graze it all the way back to the infant stage (with just a stubble of grass).
The pasture is managed so that once the grass gets set back by grazing, the cows move on, encouraging the plant to grow and pull more carbon out of the atmosphere. The cows don’t return until the grass is once again about to set seed in the “senior” stage.
Here’s another way of thinking about it: Imagine that at the teenage/adult life stage the grass is running a race and breathing hard. This is good for the soil. Part of the biomass that goes into building the roots, stem, and leaves is actually coming out of the air.
The fate of that carbon resource is now in the hands of the landowner where the photosynthesis took place. If no pig or cow grazes it, that carbon being held temporarily in the body of the plant decomposes. When it decomposes it releases that carbon back into the atmosphere. Its presence in a terrestrial environment was a “flash in the pan”. There and now gone.
Without grazing animals to continually hit the “reset” button on grass, they will act as an invisible geyser of carbon. Mining it out of the soil and throwing it into the sky. This is one of the drivers of desertification.
Nothing in any ecosystem is staying the same. It is either getting better or worse but, it is not static. Large grazing animals are the answer to improving grasslands.
This is why land needs animals like flowers need bees. In a very real sense, the cows are “pollinating” the landscape. Making it greener, cooler and more resilient.