HIR is one of the most widely used methods under the Australian Emissions Reduction Fund. Here's how carbon is measured, what obligations it creates, and how Pryleaf handles every step automatically.
Human Induced Regeneration projects generate ACCUs by allowing previously cleared or degraded land to revert to native forest. There's no planting — the existing seed bank and root mass do the work. The project holder's job is to remove the barriers to regeneration (principally: grazing pressure) and maintain those conditions across the crediting period.
To be eligible, land must have been cleared before 1990, must not have been previously registered under another carbon project, and must demonstrate that natural regeneration would not occur without the intervention (the “additionality” requirement).
HIR relies entirely on natural seed dispersal and root suckering. You do not need to plant or seed the project area.
ACCUs are earned across a 25-year crediting period. Carbon accumulation is typically front-loaded in early years as the first regrowth cohort establishes.
Once registered, the project area must be maintained as forest. Projects elect either a 25-year or 100-year permanence period — the latter attracts higher ACCU yields.
HIR has real obligations that must be met and documented every six months. These aren't just paperwork — they're conditions of your project's continued operation. Pryleaf's period checklist ensures none are missed.
Grazing is the primary management lever in a HIR project. Stock must be managed so that grazing pressure does not prevent regeneration. The CER prescribes a grazing safety calculator — based on Johnston et al. (1996) — that determines safe stocking rates from AussieGRASS forage data. Pryleaf runs this automatically each period.
The Carbon Estimation Area (CEA) — the part of your project area used for carbon accounting — must not be mechanically or chemically cleared. No dozers, no herbicide spraying of woody vegetation. Evidence of compliance is required each reporting period.
Applying fertiliser or lime within the CEA changes the nutrient dynamics of the soil and is a compliance breach. This obligation persists across the full crediting period.
Each period, you must carry out at least one activity from the Fire Management and Permanence Planning (FMPP) checklist — maintaining firebreaks, servicing fire equipment, checking and maintaining waterpoints, managing powerline buffers. Evidence required.
Net abatement is the difference between the carbon stored in your project and the carbon that would have been stored if you had done nothing (the “baseline”). The calculation is deterministic — same inputs, same output, every time.
Used for projects registered before 1 July 2016. RMT models the above-ground biomass of regrowing native forest using rainfall and soils data, calibrated against the project's specific vegetation community. Warrego (ERF101907) uses RMT.
RMT outputs a net abatement figure in tonnes CO₂ equivalent. Pryleaf runs RMT automatically and packages the model output files (.rmd) for CER submission.
Used for projects registered from 1 July 2016 onwards. FullCAM is a more comprehensive model that accounts for above-ground biomass, below- ground biomass, dead organic matter, and soil carbon across the full project area.
Pryleaf uses the correct model for each project automatically, based on registration date. Projects can't switch between models.
At years 5, 10, and 15, the CER assesses whether your project area is developing as expected. A project that fails a gateway check has its ACCU issuance suspended until it can demonstrate recovery. Pryleaf tracks your trajectory against benchmark thresholds throughout — not just at check time.
The CER verifies that the project area shows evidence of woody regeneration. Remote sensing analysis (Landsat imagery) of the CEA. Projects that fail to show sufficient cover may have their crediting paused.
Vegetation density and canopy cover assessed against the benchmark for the vegetation community. By year 10, a well-managed HIR project should show established regrowth across the CEA.
Final gateway before the back half of the crediting period. Projects must demonstrate ongoing carbon accumulation. Trajectory data from years 1–15 is reviewed alongside the current cover assessment.
Climate Friendly and other intermediaries charge up to 20% of your ACCU yield to do everything below. Pryleaf does the same work, for a fraction of the cost, with a full audit trail you can inspect at any time.