Article summary: Carbon is suddenly “in the room” again, from markets to customer requirements. A long-term NSW temperate pasture trial suggests managed grazing can incrementally increase soil organic carbon versus continuous grazing, but most of the movement still comes from bigger forces like seasons and land-use history. Here’s what that likely means on-farm, and the practical traps to avoid before you change your system.
Why this matters right now (even if you are not chasing carbon)
If you farm in a temperate pasture system, you’ve probably noticed the conversation shifting.
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Carbon markets are getting more attention.
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Buyers and supply chains are increasingly asking for proof of lower emissions, better land condition, or “insetting” style improvements.
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Risk management is front and centre: plenty of producers are already adjusting grazing to protect groundcover, keep options open in a dry spell, and avoid blowing up a rotation when conditions turn.
So the question is not “should you chase carbon?” It’s more practical than that:
If you improve grazing management anyway, does soil carbon tend to follow? And what could trip you up when you try to measure it?
A long-term NSW temperate pasture trial gives a useful, balanced answer.
What the NSW temperate pasture trial found (in plain English)
A NSW Department of Primary Industries and Regional Development (NSW DPIRD) study in temperate pastures reported that managed grazing increased soil organic carbon (SOC) compared to continuous grazing, but also made a key point:
Seasonal conditions and land-use change had a much bigger influence than grazing management alone.
Some of the headline findings reported:
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Systems with rest periods around 56 days and 15 paddocks had higher SOC stocks than continuous grazing, but doubling rest length or paddock numbers didn’t increase sequestration further.
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Low starting soil carbon responded the most: the study reported an average capture of 0.77 t C/ha/year, up to 1.22 t C/ha/year in “optimal conditions”.
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Sequestration was reported to continue during drought, but at a much lower rate (0.13 t C/ha/year).
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The study estimated that improved grazing management itself contributed about 0.1 t C/ha/year, with the rest driven by environmental factors and land-use change.
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Bare ground was a strong predictor: more bare ground was associated with lower SOC, reinforcing the “groundcover first” message.
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Interestingly, high stocking rates did not shift soil carbon compared to low stocking rates in this work.
The underlying paper (reported as a long-term trial established in 2012, with SOC sampled about every three years to 30 cm) also notes that a large share of SOC increase can reflect land-use conversion history, not just grazing tweaks.
Translating “t C/ha/year” into something you can picture
It’s easy to hear “0.1 tonnes per hectare per year” and think that sounds big. It’s worth grounding it.
0.1 t C/ha/year = 100 kg of carbon per hectare per year.
That’s about 10 grams of carbon per square metre per year (a thin sprinkle, not a thick layer).
In CO₂ terms (because markets often talk CO₂e), 1 tonne of carbon is about 3.67 tonnes of CO₂. So:
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0.1 t C/ha/year ≈ 0.37 t CO₂e/ha/year
On a 100 ha block, that’s ~37 t CO₂e/year if it was real, measurable, and credited. But here’s the catch:
That 0.1 t C/ha/year is an average estimate of the grazing-management effect, and it will not show up neatly every year, in every paddock, at every depth.
So treat the numbers like a directional indicator, not a guaranteed income stream.
The practical takeaway: “carbon-friendly” grazing is mostly just good grazing
Across studies, the most consistent drivers of building (or at least not losing) SOC are the boring fundamentals:
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Keep groundcover high.
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Grow more total pasture (more photosynthesis = more potential carbon inputs).
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Push more carbon below ground (roots and root turnover matter a lot).
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Avoid management that causes erosion, compaction, or long bare periods.
The Australian review literature makes a similar point: while direct SOC gains from grazing management are hard to prove consistently, lower stocking intensity and/or built-in rest periods often improve herbage mass and groundcover, which are key “upstream” drivers of SOC.
What that can look like on-farm (without pretending there’s one right system)
If your goal is to tilt the odds toward better SOC outcomes while still running a profitable grazing business, “managed grazing” usually means:
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Shorter graze periods (reduce repeated bites, protect regrowth points).
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Rest matched to growth (fast spring growth = shorter rest; slow winter/dry = longer rest).
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Residual discipline (leave enough leaf to regrow, and enough cover to protect soil).
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Stocking flexibility (because rigid stocking is where good intentions die in a hard season).
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Triggers for action (e.g., “if groundcover drops below X, we destock or change plan”).
The NSW work highlighting bare ground as a strong predictor is a good reminder: if your “carbon strategy” creates more bare ground during pinch periods, it is probably moving you the wrong way.
Where pasture species mix fits (and why it can matter)
Grazing management is only one lever. Pasture composition can change how much carbon gets into the soil, and where it goes.
The Australian review summarises key pathways that can help SOC accumulation, including:
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promoting deep-rooted perennial plants
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increasing plant and root growth
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increasing nitrogen inputs via legumes
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maintaining groundcover to reduce erosion and support soil structure
In practical terms, that means:
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A pasture base with persistent perennials can help keep roots active across more of the year.
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Legumes can lift total growth (and improve feed quality), but only if soil fertility and grazing management allow them to persist.
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In some soils and climates, species choice influences whether carbon gains stay mostly in the top 0–10 cm or push deeper (deeper carbon is often considered more stable).
A nice reality check from the Soil CRC work in southern NSW: rainfall patterns strongly influence soil carbon changes, and most increases tend to show in the top 0–10 cm, with drought able to pull values back.
Where the traps are (measurement and management)
This is the section most carbon conversations skip.
Trap 1: Confusing “land-use change” with “grazing effect”
If a paddock has moved from cropping, run-down pasture, or bare fallow periods into a productive perennial pasture phase, SOC can rise strongly regardless of the finer points of rotation.
That’s why the NSW results explicitly note that environment and land-use history explained most of the change, with managed grazing adding a smaller incremental lift.
Trap 2: Depth, bulk density, and sampling consistency
SOC is not evenly distributed with depth, and it is easy to accidentally “find” gains (or losses) by sampling differently.
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Different projects use different depths (0–10, 0–30, 0–50 cm).
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You also need bulk density to convert %C into stocks properly.
Global reviews have highlighted that inconsistent soil depths across studies creates contradictory results, which is why some analyses normalise results to a standard depth (often 30 cm) to compare properly.
Trap 3: Expecting a straight line year-to-year
Soil carbon does not behave like a bank account with steady deposits.
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Big growing seasons can drive gains.
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Droughts, floods, bare periods and erosion can erase them.
Soil CRC guidance for southern NSW puts it bluntly: SOC increases align strongly with rainfall, drought can decrease values, and each soil has a stable carbon storage capacity rather than an endless linear increase.
Trap 4: “Intensity” without control becomes bare ground
The NSW study’s “bare ground matters” finding should shape your planning.
If your system relies on:
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high utilisation targets
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fixed rest periods
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and no exit plan when growth collapses
…then it can look great until it doesn’t. Soil carbon is unlikely to improve if the strategy increases soil exposure or erosion risk.
Trap 5: Thinking grazing can outrun soil constraints
If fertility, pH, compaction, drainage, or salinity limit plant growth, you are limiting the engine that feeds carbon into the soil.
The Soil CRC fact sheet stresses managing constraints (like acidity, compaction, drainage) and maintaining fertility so plants can actually grow enough biomass to shift SOC over time.
Box: 3 questions to ask before changing your grazing system
Before you invest in more subdivision, longer rotations, or a “carbon-focused” grazing plan, ask yourself:
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What soil type are you working with, and what’s your starting point?
Some soils have more “headroom” than others, and low baseline SOC tends to respond more strongly than high baseline SOC. -
How reliable is your rainfall and growth pattern?
SOC movement often tracks seasons. If your rainfall is highly variable, your carbon trend will be lumpy too. -
How much stocking flexibility do you actually have?
The best grazing plan fails when you cannot destock, adjust classes of stock, change feed plans, or protect groundcover quickly enough.
If you do not like your answers to these three questions, start smaller and focus on the constraints first.
A sensible way to “trial” managed grazing without betting the farm
If you want to move in this direction, you’ll usually get better outcomes by running it like a farm systems change, not a belief system.
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Pick a representative area (not your best paddock).
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Define 2–3 measurable outcomes you care about (groundcover, residuals, pasture utilisation, days of feed ahead, animal performance).
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Record grazing and recovery consistently for at least a full seasonal cycle.
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Aim for fewer preventable bare-ground events, especially during pinch periods.
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If you are serious about SOC measurement, get professional sampling advice so you don’t waste years of effort on noisy data.
The point is to build a system that is profitable and resilient first, with carbon as a potential co-benefit.
Where Pasture.io fits (keeping the system measurable)
Managed grazing only works when you can see the rotation and respond early.
Whether you use Pasture.io or another system, the practical need is the same:
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you need to track grazing events
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see what’s coming up vs what’s ready
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and make calls early enough to protect residuals and groundcover
That’s often the difference between “managed grazing that improves the whole system” and “managed grazing that looks good on paper but blows out in a tough month”.
Bottom line
The NSW temperate pasture trial suggests managed grazing can incrementally lift soil carbon compared to continuous grazing, but it also reinforces a hard truth:
Seasons, land-use history, baseline carbon, and measurement choices can swamp the management signal.
If you focus on groundcover, growth, and flexibility, you’re improving the fundamentals that SOC depends on anyway. Just be careful about the traps, especially measurement depth, baselines, and expecting tidy year-by-year results.
- The Dedicated Team of Pasture.io, 2025-10-09