The Carbon Grazing Principle
The model
Sustainable land management is achieved by understanding principles, not implementing recipes. Principles do not change, it is circumstances that change. Principles supply guidance on how to adapt to different circumstances. Engineers are taught all the principles before being sent out into the real world, so why should graziers be any different. Importantly, principles have to be simple and easy to understand. They are always easier to remember if you understand the why as well as the how.
The discussion has been slowly building the principles behind the Carbon Grazing concept. Now is the time to formalise it into an action plan. Carbon Grazing is the removal of livestock from pastures for 4-6 weeks after pasture growing rain. This is a general principle, so it is important to not get caught up on the exact time, as there will always be variables such temperature.
Pasture rest is long enough if the perennial plants are able to replenish their energy reserves and annuals succeed in setting enough seed for the future. This need not actually occur during the rest period, but it must happen as a result of the rest.
The obvious has to be stated, in that livestock do not consume all the plants the first day they are re-introduced to pastures. Therefore, even for the most palatable plants, the actual rest time will always be longer than the exclusion time of animals. The more the most palatable plants have bulked up, the more they remove grazing pressure off each other when domestic animals are returned to the pastures.
Carbon Grazing is a general principle and addresses the mechanics of all the processes that contribute to how the landscape operates. It is about maximising carbon flows when the opportunities arise. It is about understanding why carbon needs to be allowed to flow through all the components of the landscape both above and below the ground. It is about managing animals so that they cannot excessively limit photosynthesis. It is also a simple management processes that ensures animals do not eliminate the most productive plants in the pasture.
The concept sets out to meet the needs of animals as well as the needs of the plants and the soil. It is about achieving balance in all the factors of production, as an enterprise will fail if any factor of production is not maintained. The actions required to maintain profit are the same as those required to maintain the environment.
It is important to realise that the actual rest period does not start until the plants begin to respond to rainfall, not necessarily the day after the rain. This aspect of the model is consistent with the practical issues of shifting animals.
The principle of Carbon Grazing is "strategic / tactical rest" and is based on the premise that nature does not have a predictable pattern. It is all about following the instructions of nature. Strategic rest improves the natural resource base because it coincides with when nature wants to grow plants and regenerate the landscape through all the processes that occur with plant growth. Stated simply, we must allow nature to transfer carbon from the atmosphere to the landscape according to it's time frame. Carbon Grazing is not based on what might happen, but what is about to happen. Natures' instructions never go astray, as they are always left in the rain gauge.
The logic of "rest after rainfall" is that moisture triggers processes in plants and soil organisms. Nature has designed the system so that water activates the storage of carbon in the landscape via photosynthesis. Water also activates the soil biota to release nitrogen, other nutrients, and growth promo ants to help plants grow. Nitrogen is subject to loss through leaching or amonification, if not used when it is available (i.e. can escape the system if not used immediately by plants). Timing is the important issue because plants are activated by moisture, as are soil microbes. Carbon Grazing is based on the premise that pasture rest is TIMING and not TIME.
Resting for set periods of time when it is not raining is a consumption issue, not a production and regeneration issue. This must not be confused with strategic / tactical rest. The exception is when a regeneration event has occurred and freshly germinated seedlings need to be protected to allow them to establish. As a separate issue, when landscapes become bare, there may be the need to remove animals to protect them.
The previous section, "Is pasture rest time or timing?" highlights the importance of allowing carbon to flow from the atmosphere into the landscape after rainfall. On the positive side, it is moisture that instigates photosynthesis. However, on the negative side, it is moisture that can deplete the energy reserves held in the roots of perennial plants. This is because plants will keep trying to grow while there is moisture. If animals are allowed to consume all the above ground growth every time plants emerge from dormancy, then the plants are forced to keep drawing on their energy reserves to promote growth. Given that plants will keep trying to grow when there is moisture and warmth available, it is possible for their energy reserves to be exhausted.
Understanding the principle, "it is the last straw that breaks the camel's back", really applies to plant survival, when energy reserves get too low. This is the point CSIRO scientist, David Freudenberger makes, when he refers to the paradox of average years. Perennial grasses are in and out of dormancy in average years, whereas they do not call on energy reserves in droughts.
One of the core messages of Carbon Grazing is that short term rest achieves long term outcomes as well as short term outcomes. There is the obvious short term gain of increased pasture production for animal consumption when plants are allowed to grow. In the short term there is also an increased flow of energy via plant roots to support the regenerative processes occurring in the soil. Taking a longer term view, the increase in photosynthesis adds to the total carbon pool together with the long term accrued benefits. Again looking to the longer term, with the next opening rains, the currently rested plants with higher energy reserves and larger root systems, will respond quicker and more vigorously. Healthy plants can also respond to marginal falls, whereas unhealthy plants in unhealthy soil show no response. If plants are being stressed from ongoing lack of rain, then it is plants which have been allowed to grow after previous rain, that are less likely to die, now or in the near future if the season continues to deteriorate.
In summarising the main issues, it is important to separate the two distinct outcomes of rest. The first is stopping the depletion of energy reserves in the roots as perennial plants leave dormancy. The second is allowing all the processes associated with plant growth to occur, which includes replenishing energy reserves, and building an extensive root system capable of sourcing moisture and nutrients over a larger volume of soil. It also includes allowing soil organisms to restructure the soil so it remains healthy and productive.
In a perfect world, every opportunity to rest would be taken advantage of, but this is not always practical. The focus has to be on maintaining energy reserves over time, in the same way we must maintain soil condition. It is our overall actions that count. This is why it was stated earlier. "Just as it is important to keep the bank account in the black, so the carbon balance on a property must also be in the black. Farmers can borrow and pay back from this carbon account, but borrowing more than you pay back leads to ecological poverty, followed closely by economic poverty." A single action can be the catalyst to start taking a landscape forward, but it is unlikely a single action would ever bring a healthy landscape to its knees.
In Australia we are never sure whether useful rain, is the first of many falls, or an isolated event with no followup for a considerable time. This is even more so, in the arid rangelands where the cycle of nature is slower. This uncertainty of what the future holds, dictates that a pasture management model has "one action plan" that is consistent with both possibilities. The response to useful rain has to achieve many outcomes including maximising pasture production, pasture and soil regeneration, as well as postponing the return of drought, reducing future plant death and animal stress, and stoping soil deterioration.
How often people choose to apply the principle of Carbon Grazing is determined by the number of suitable events nature supplies, and more importantly, how often producers are in the position to be able to remove livestock from pastures. The chapter on "Techniques for spelling" looks at this issue. People in higher rainfall areas are blessed with more opportunities for spelling than those in the arid areas. Therefore, producers in lower rainfall areas pay a higher price for missed opportunities.
Quantifying increases in production and hence carbon
The South African rangeland scientists I have dealt with are very focused on rest after rainfall. While visiting their country, they explained that with average pastures, 3-8 weeks of rest after rain can see an increase in pasture production of 50-80%. At the time when pastures are emerging from dormancy, there is the potential for so much lost production.
Conclusion
The smart operators think about drought when it rains.
To download a PDF version of Chapter 16: The Carbon Grazing Principle of "Carbon Grazing - the missing link" (file size 497Kb), click on the highlighted chapter heading.
To purchase a hard copy version of "Carbon Grazing - the missing link" click on the highlighted book title.
return to top