ART TREES 3.0: Updates to Jurisdictional REDD+ Crediting

This is a new issue of newsletter from Deloitte Tohmatsu Sustainacraft.

Methodology Updates is a series on developments in carbon and biodiversity credit methodologies. This article examines the recently updated jurisdictional REDD+ ART TREES 3.0 standard, and what its revisions mean for how credits are issued.

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Author: Nick Lau (Applied Scientist)

Summary

The Architecture for REDD+ Transactions (ART) released Version 3.0 of its REDD+ Environmental Excellence Standard (TREES) in June 2026. TREES credits forest emissions reductions and removals across national or eligible subnational jurisdictions rather than attributing each outcome to an individual conservation project. The revision builds on this established accounting framework while changing access to participation, the justification of crediting levels, restoration accounting and the adjustments applied before issuance.

The most consequential developments are a time-limited pathway for existing REDD+ programs and eligible jurisdictions, an additional demonstration of conservativeness in emissions and HFLD crediting, and a sample-based option for natural forest restoration. Revised uncertainty and reversal-risk procedures also affect how reported carbon outcomes become credits. These changes broaden some routes to participation and crediting while adding or clarifying requirements intended to limit over-crediting.

This article explains the principal revisions in TREES 3.0 alongside the existing accounting rules retained from TREES 2.0, with particular attention to the distinction between a quantified forest carbon outcome and a credit eligible for issuance.

1. Jurisdictional REDD+ and ART TREES

1.1 Project-based and jurisdictional REDD+

Project-based REDD+ typically credits emissions reductions associated with conservation activities in a defined forest area. Depending on the methodology, the project establishes a counterfactual using historical trends, reference areas or deforestation-risk models, then compares expected emissions with observed outcomes.

Jurisdictional REDD+ instead evaluates aggregate forest emissions across a country or eligible subnational territory against a common crediting level, rather than assigning each reduction to a specific conservation activity. A jurisdictional result therefore reflects the combined effects of land-use policy, enforcement, protected areas, community forestry, agricultural expansion and other changes within the accounting area.

The larger boundary also changes the treatment of displaced deforestation. If clearing shifts between districts within the same jurisdiction, the resulting emissions remain in the reported total. Displacement beyond the boundary of a subnational jurisdiction can still require a leakage deduction. Other conceptual differences between jurisdictional and project-based REDD+ are summarized in the following table.

1.2 The ART TREES framework

The Architecture for REDD+ Transactions (ART) is an independent carbon crediting program for jurisdictional forest emissions reductions and removals. Its REDD+ Environmental Excellence Standard (TREES) defines the accounting, monitoring, verification and safeguard requirements under which national and eligible subnational governments can obtain serialized credits for verified results.

The core accounting model remains largely intact from TREES 2.0. Each five-year crediting period uses recent historical forest emissions as the principal benchmark for assessing reductions, with a separate option for high-forest, low-deforestation (HFLD) jurisdictions. Eligible conversion of non-forest land back to forest is accounted for as removals. Results are quantified across the accounting area, verified, and then adjusted for leakage, uncertainty and reversal risk before issuance. Version 3.0 does not replace these elements; its main changes concern which jurisdictions can participate, how crediting levels and removals are justified, and how eligible issuance is calculated.

1.3 Participation and the Transition Pathway

TREES' ordinary subnational eligibility rules require sizeable forest areas and accounting boundaries that follow specified jurisdictions or recognized Indigenous territories. These conditions can be difficult for existing REDD+ programs whose reporting areas were designed under other frameworks, or for jurisdictions with relatively little forest. To accommodate them, TREES 3.0 introduces a time-limited Transition Pathway, intended to ease the transition of FCPF Carbon Fund and ISFL programs to ART. Participants in these programs may retain their existing accounting areas for an initial crediting period. Other eligible participants, including certain smaller forest countries and jurisdictions with prior REDD+ involvement, may qualify under a lower forest-area threshold. The pathway does not waive TREES' other accounting and safeguard requirements.

Both routes require acceptance of a TREES Concept by the end of 2028 and are available only through 2035. Separately, the deadline for interim subnational accounting moves from 2030 under TREES 2.0 to the end of 2035. National government participation and reporting are required thereafter, although crediting may continue for subnational areas within national participation. The changes offer existing programs more time and routes to enter ART without making subnational accounting a permanent substitute for national reporting. Credits issued using an eligible accounting-area exception carry a Transition Pathway label.

2. Establishing the Crediting Level

2.1 Historical emissions and performance-based additionality

For emissions reductions, TREES retains the preceding five-year average of emissions from deforestation and degradation as its starting point. Under TREES 2.0, that historical average generally formed the crediting level. The revised rules instead reduce it by 1% by default, unless a participant provides quantitative evidence that the unadjusted average is already conservative relative to expected emissions threats. The adjustment responds to the requirement to set a benchmark below business-as-usual rather than assuming that historical emissions necessarily meet that test.

Suppose a jurisdiction averaged 10 million tCO₂e in annual forest emissions during the reference period. The default adjustment sets its crediting level at 9.9 million tCO₂e. If monitored emissions are 8 million tCO₂e in a crediting year, the gross reduction is 1.9 million tCO₂e before issuance deductions and buffer contributions. At renewal, the crediting level normally cannot rise, except when newly included carbon pools or activities change the scope of the accounting.

Additionality is thus assessed through jurisdiction-wide performance against a common benchmark, not through separate estimates of the emissions avoided by individual enforcement measures, protected areas or community initiatives. This avoids intervention-level counterfactual calculations but does not identify which actions caused the reported reduction. Historical forest clearing may reflect unusual conditions, while commodity markets, climate and land-use policy can affect emissions during the crediting period. The new adjustment makes the historical benchmark more conservative without establishing with certainty what would have occurred in the absence of the program.

2.2 High forest, low deforestation approach

Jurisdictions with extensive forests and historically low deforestation have limited opportunities to generate reductions against an already low historical benchmark. TREES therefore retains its optional high-forest, low-deforestation (HFLD) approach, which allows qualifying jurisdictions to receive credits for maintaining low emissions even where further reductions against their historical level are small. Eligibility is determined by a score combining forest cover and deforestation rates.

The HFLD crediting level adds a small allowance to the ordinary historical emissions benchmark, calculated from the jurisdiction's HFLD score and 0.05% of standing forest carbon stock. The allowance is a proxy for emissions threats to existing forests rather than a direct measurement of avoided deforestation. Its significance is that maintaining low emissions may generate credits even without a large decline from the jurisdiction's own historical emissions.

The main revision is in how this higher crediting level must be justified. TREES 2.0 treated jurisdictions meeting the HFLD eligibility threshold as additional; TREES 3.0 retains an eligibility-based test but also requires documentation of relevant REDD+ activities during the reference period and quantitative evidence that the HFLD crediting level is conservative relative to the threat of emissions. High forest cover and low historical deforestation therefore do not, by themselves, substantiate the size of the allowance. Deductions continue to increase when annual emissions rise above the ordinary benchmark, with HFLD crediting ending if the increase becomes sufficiently large.