Cows on pasture seems like a pretty simple system. Cows eat grass and their manure helps feed the soil which helps the grass to grow again. What many ranchers have found is that if you plan the grazing to give enough recovery time for the grass roots to grow back, you get healthier pasture and can actually grow soil as a result. So how does that work?
When a grass plant is bitten, the roots recede to power the leaf growth. In a planned grazing system, we allow for the recovery of the roots so that growth is regenerative. In a conventional pasture, where the cattle are allowed to roam anywhere they want, the grass plants can get stunted due to over grazing. As I mentioned above, when a grass plant is bitten, the roots shrink up to give the plant energy to grow the leaves again. If the grass is bitten before the roots recover, the roots try and provide the growth again, which shrinks them even more. Since there wasn’t much energy left in the recovering roots, the grass can only grow a little bit. Eventually, the grass plant becomes stunted and the pasture underperforms. Little roots and little shoots equals stunted pasture.
Healthy grass does a number of wonderful things for the ecosystem by providing root exudates for the soil microbes to actually grow soil. Root exudates are sugars, organic acids, and other carbon compounds that the plant sends through the roots to provide the bacteria and fungi an incentive to deliver much needed nutrients and water to the plant. Carbon is the currency that plants use to grow. As this process plays out, carbon is extracted from the air through photosynthesis and the plant sends it into the ground. This is a really powerful process that builds the organic matter in our soils and sequesters carbon. By increasing the carbon in the soil, we are decreasing it from our atmosphere and, as we can see, Carbon dioxide has been increasing in our atmosphere ever since the industrial revolution. As we burn fossil fuels and over till soils, we are releasing it into the atmosphere and the ocean can only absorb so much.
One way we can balance this out is by growing topsoil through the use of techniques like planned grazing practices. Giving enough time for the roots to recover keeps the incentive system working. The microbes are happy, the plants are happy, and in turn, the cattle are happy. All while pulling carbon from the air and putting it in the ground.
All of this is great stuff, but in some cases where the land has been mismanaged or through some other undesirable type of environmental condition, the land might need a jumpstart to get back to good health. Marin Carbon Project has been doing some amazing work with applying compost to rangelands and found that just one application of 1/2” of compost to a pasture can assist the pasture plants in getting the party going underground again stimulating growth, increasing water holding capacity, and most importantly, carbon sequestration.
We are experimenting with applying compost to our pastures in combination with planned grazing to see how this will improve the performance of the land. We started applying the compost on the land about a month ago and then the el niño rains hit us. We are hoping to get more compost out into some other trial areas once we can get back out into the soggy pastures. We believe that through MCP’s great work and with the planned grazing, we can possibly increase the carbon sequestration and performance of the land as a win-win for everyone involved. From the smallest organisms to the big bovines, everyone has a job in the ecosystem. Stay tuned as we work with our friends from Point Blue to help us monitor and record the results here on TomKat Ranch. We’ll share what we find!
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