This page last reviewed December 2, 2015

Compliance Offset Protocol U.S. Forest Offset Projects

Adopted November 14, 2014

This page describes the ARB Compliance Offset Protocol for U.S. Forest Projects adopted November 14, 2014 (2014 Forest Protocol) and all supporting documents for project implementation.  The calculations for estimating volume and converting biomass to CO2e vary by project location.  Forest projects may be located anywhere in the lower 48 states.  Forest land in Alaska, Hawaii, and the U.S. Territories are not eligible at this time.  Projects listed under the 2014 Forest Protocol located in California, Oregon, and Washington should refer to Table 1.  Projects listed under the 2014 Forest Protocol located within the other 45 contiguous states should refer to Table 2.  

Projects listed under the June 25, 2015 Compliance Offset Protocol for U.S. Forest Projects should refer to that version's U.S. Forest Offset Projects webpage.

Projects listed under the October 20, 2011 Compliance Offset Protocol for U.S. Forest Projects should refer to that version's U.S. Forest Offset Projects webpage.

Skip to: Approved Growth and Yield Models

Skip to: Guidance in the form of Frequently Asked Questions

Skip to: Guidance for U.S. Forest Projects Transitioning from Early Action to Compliance 

Skip to: Compliance Offset Program Forms to obtain forest offset project listing forms and forest Offset Project Data Report forms

Introduction

The Forest Protocol provides requirements and methods for quantifying the net climate benefits of activities that sequester carbon on forestland. The protocol provides offset project eligibility rules; methods to calculate an offset project’s net effects on greenhouse gas (GHG) emissions and removals of CO2 from the atmosphere (removals); procedures for assessing the risk that carbon sequestered by a project may be reversed (i.e. released back to the atmosphere); and approaches for long-term project monitoring and reporting. The protocol is designed to ensure that the net GHG reductions and GHG removal enhancements caused by an offset project are accounted for in a complete, consistent, transparent, accurate, and conservative manner and may therefore be reported as the basis for issuing ARB or registry offset credits.

Offset Project Operators or Authorized Project Designees must use the 2011 Forest Protocol for projects listed no later than midnight December 31, 2014 to quantify and report GHG reductions and GHG removal enhancements. For projects listed on or after January 1, 2015, Offset Project Operators or Authorized Project Designees must use the 2014 Forest Protocol to quantify and report GHG reductions and GHG removal enhancements.

The protocol provides eligibility rules, methods to quantify GHG reductions, project-monitoring instructions, and procedures for reporting Offset Project Data Reports. Additionally, all offset projects must submit to independent verification by ARB-accredited verification bodies. Requirements for verification bodies to verify Offset Project Data Reports are provided in the Cap-and-Trade Regulation. 

ARB Video: "California's forest offset protocol" (CAFR5011--Yurok project)

ARB Video: "Forest offset project benefits tribes and state" (CAFR5028--Round Valley project)

U.S. Forest Protocol Resources

Compliance Offset Protocol U.S. Forest Projects (Forest Offset Protocol)pdf (PDF - 1.15MB)

Table 1: Documents for Projects Located in California, Oregon, and Washington

Description

Instructions





The Forest Protocol requires estimates of total above-ground and below-ground biomass. Offset Project Operators (OPOs)/Authorized Project Designees (APDs) with projects located in California, Oregon, and Washington should use these instructions to convert biomass to tons of CO2e emissions or removal enhancements.
Supersection Maps:




Supersection MapStep 1:  Supersection maps identify the appropriate Supersection and Assessment Area corresponding to the project’s location.  An OPO/APD must first determine the geographic Supersection within which the Project Area is located by reviewing the Supersection maps.  A GIS shapefile of the Supersection may be downloaded to map the project boundaries for reporting purposes.  
Assessment Area Data File






Step 2:  After the OPO/APD identifies the correct Supersection for its Project Area, the OPO/APD must consult the Assessment Area Data File to identify the Assessment Area that best corresponds to the project, based on the dominant vegetation present in the "forest type" category within the spreadsheet.  The Assessment Area Data File provides information that must be used as inputs to meet Protocol requirements.  Click here for more details on the categories contained in the Assessment Area Data File.
Volume Estimation and Biomass Equations - Projects Located in California, Oregon, and Washington



Step 3a:  The OPO/APD must find and use references and coefficients associated with each species in a Project Area for projects located in CA, OR, and WA.  The volume equation references and coefficients in this document must be used in conjunction with the biomass equations provided for CA, OR, and WA (referenced in Step 3b).

Step 3b:  The OPO/APD must use the biomass equations presented in this document for projects located in CA, OR, and WA.  Biomass equations have been obtained from the U.S. Forest Service FIA National Program.  These biomass equations must be used in conjunction with the volume equation references and coefficients by species for projects located in CA, OR, and WA (referenced in Step 3a).
Estimating Carbon in Wood Products
















Step 4:  For projects that include harvesting, the OPO/APD must estimate the carbon stored in harvested wood products. The following documents are needed to estimate carbon in harvested wood products:

Step 4a:  Regional Mill Efficiency Data
The OPO/APD must identify the mill efficiency factor and use that factor as an input to estimate carbon in harvested wood delivered to mills.  

Step 4b:  Table C.1 Specific Gravity and Wood Density by Forest Type for CA, OR, and WA
The OPO/APD must check Table C.1 (duplicate of table on page 97 of the Protocol), which provides gravity and wood density factors by forest type.  Once the forest type is identified, these factors are used as an input to help determine the carbon in harvested wood delivered to mills.   

Step 4c:  Wood Product Classes
The OPO/APD will need to estimate the average carbon stored over 100 years in in-use wood products.  The OPO/APD may do this using the Supersection default values in the “Wood Products Generated” worksheet within the Assessment Area Data File or by obtaining a verified report from the mill(s) where the Project Area’s logs are sold indicating the product categories the mill(s) sold for the year in question.



Table 2: Documents for Projects Located Within the Other 45 Contiguous States (Outside California, Oregon, and Washington)

Description

Instructions


















The Forest Protocol requires estimates of total above-ground and below-ground biomass. Offset Project Operators (OPOs)/Authorized Project Designees (APDs) with projects located in all approved states except California, Oregon, and Washington (lower 45 states) should use these instructions to estimate volume and convert biomass to tons of CO2e emissions or removal enhancements.  The Protocol requires use of specific volume equations found in "Methods and Equations for Estimating Aboveground Volume, Biomass, and Carbon for Trees in the U.S. Forest Inventory, 2010" . Coefficients are found in the regional Coefficients Database associated with the Woodall document. OPOs/APDs must estimate biomass using the Component Ratio Method (CRM); the CRM is applicable to all states except California, Oregon, and Washington. 
Supersection Maps


Supersection MapStep 1:  An OPO/APD must first determine the geographic Supersection within which the project area is located by reviewing the Supersection maps in this table.  Supersection maps identify the appropriate Supersection and Assessment Area corresponding to the project’s location.  A GIS shapefile of the Supersection may be downloaded to map the project boundaries for reporting purposes. 
Assessment Area Data File




Step 2:  After the OPO/APD identifies the correct Supersection for its Project Area, the OPO/APD must consult the Assessment Area Data File to identify the Assessment Area that best corresponds to the project, based on the dominant vegetation present in the ‘forest type’ category within the document.  The Assessment Area Data File provides information that must be used as inputs to meet Protocol requirements.  Click here for more details on the categories contained in the Assessment Area Data File.
Volume Estimation and Biomass Equations - Projects Located Outside of California, Oregon, and Washington



































Step 3a: The "Methods and Equations for Estimating Aboveground Volume, Biomass, and Carbon for Trees in the U.S. Forest Inventory, 2010" document provides cubic foot gross and sound volume models for the 45 states by region and species1.  The OPO/APD will need the accompanying “Coefficients Database” to determine the correct coefficients to use for gross and/or sound volume. 

Step 3b: Use the Coefficients Database to find the appropriate coefficients by project location and species.  Coefficients for the same species may be different in two different locations.  Gross cubic foot volume (VOLCFGRS) must be converted to sound cubic foot volume (VOLCFSND) by subtracting rotten and missing cull volume.

Step 3c:
The standing dead tree carbon pool must be adjusted for density reduction and structural loss using the approach established in "Accounting for density reduction and structural loss in standing dead trees: Implications for forest biomass and carbon stock estimates in the United States." General guidance for using the Domke method is found here.

Decay class, density reductions factors (DRFs), and structural loss adjustment (SLA) factors are necessary to complete calculations for standing dead trees.  Decay class and DRFs are found in Appendix B of "Differences Between Standing and Downed Dead Tree Wood Density Reduction Factors: A Comparison Across Decay Classes and Tree Species" under the column labeled "SD."  Where species are not found or missing DRFs (in Appendix B), OPOs/APDs must identify a value by appropriate decay class from within the same genus (from Appendix D). If this is not possible, use the hardwood/softwood default values found in Table 6 of Harmon (2011).  OPOs/APDs should always cite the source of the DRF and column within the source for ease of verification..

SLA factors can be found in Table 2 of Domke (2011) for decay classes 1-5 for top, bark, bole, stump and roots.  These SLA factors are applicable to all species.

Biomass is then calculated for individual tree components following the Component Ratio Method.

Step 3d: The "Biomass Estimation Component Ratio Method" document is an excerpt from the FIA Database User’s Manual2 and should be used to calculate biomass for all projects outside California, Oregon, and Washington.  It provides a nationally consistent method of estimating tree biomass, called the Component Ratio Method (CRM)3.  The CRM involves calculating the dry weight of individual components before estimating the total above-ground or below-ground biomass.  The tables in this document describe the equations used to estimate various components of tree biomass (stem wood, top and branches, bark, stump, course roots).  Most components are estimated through a series of ratio equations4

The “Biomass Coefficients for Use with the Component Ratio Method” document must be used in conjunction with the document in Step 3a.  It provides the coefficients for common species that are necessary to estimate biomass using the Component Ratio Method.
Estimating Carbon in Wood Products
















Step 4a:  For projects that include harvesting, the OPO/APD must estimate the carbon stored in harvested wood products. The following documents are needed to estimate carbon in harvested wood products:

Step 4b:  Regional Mill Efficiency Data
The OPO/APD must identify the mill efficiency factor and use that factor as an input to estimate carbon in harvested wood delivered to mills.  

Step 4c: 
USFS Wood Handbook
This handbook provides gravity and wood density factors by forest type; these factors are used as input to determine the carbon in harvested wood delivered to mills.

Step 4d:  Wood Product Classes
The OPO/APD will need to estimate the average carbon stored over 100 years in in-use wood products.  The OPO/APD may do this using the Supersection default values in the “Wood Products Generated” worksheet within the Assessment Area Data File or by obtaining a verified report from the mill(s) where the Project Area’s logs are sold indicating the product categories the mill(s) sold for the year in question. 

Footnotes
[1] Cubic foot volume calculations are necessary for trees with diameters greater than or equal to 5 inches.  Trees with diameters less than 5 inches do not require cubic foot volume calculations to estimate biomass using the Component Ratio Method.  Biomass for trees less than 5 inches in DBH is calculated with DBH only following Appendix J of the "Draft Forest Inventory Analysis Database Description and Users Manual, Version 4.0, Revision 2.
[2] Appendix J. December 2009. Draft Forest Inventory Analysis Database Description and Users Manual, Version 4.0, Revision 2.
[3] Heath et al. 2009.
[4] Jenkins et al. 2003.

References

Bailey, R. G.; Avers, P. E.; King, T.; McNab, W. H., eds. 1994. Ecoregions and subregions of the United States (map). Washington, DC: USDA Forest Service. 1:7,500,000. With supplementary table of map unit descriptions, compiled and edited by W. H. McNab and R. G. Bailey.

Forest Inventory and Analysis Database 6.0.  2009.  Appendix J.  In: DRAFT FIA Database Description and Users Manual for Phase 2, version 4.0, revision 2.  U.S. Department of Agriculture, Forest Service.

Harmon, Mark E.; Woodall, Christopher W.; Fasth, Becky; Sexton, Jay; Yatkov, Misha. 2011. Differences between standing and downed dead tree wood density reduction factors: A comparison across decay classes and tree species. Res. Pap. NRS-15. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 40 p.

Heath, Linda S.; Hansen, Mark; Smith, James E.; Miles, Patrick D.; Smith, Brad W.  2009.  Investigation into calculating tree biomass and carbon in the FIADB using a biomass expansion factor approach.  In: McWilliams, Will; Moisen, Gretchen; Czaplewski, Ray, comps. 2009. 2008 Forest Inventory and Analysis (FIA) Symposium; October 21-23, 2008; Park City, UT. Proc. RMRS-P-56CD. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 26 p.

Jenkins, Jennifer C.; Chojnacky, David C.; Heath, Linda S.; Birdsey, Richard A.  2003.  National scale biomass estimators for United States tree species.  Forest Science. 49: 12-35.

McNab, W.H.; Cleland, D.T.; Freeouf, J.A.; Keys, Jr., J.E.; Nowacki, G.J.; Carpenter, C.A., comps. 2007. Description of ecological subregions: sections of the conterminous United States [CD-ROM]. Gen. Tech. Report WO-76B. Washington, DC: U.S. Department of Agriculture, Forest Service. 80 p.

U.S. Department of Agriculture, Forest Service, Forest Inventory and Analysis National Core Field Guide (October 2010)

Woodall, Christopher W.; Heath, Linda S.; Domke, Grant M.; Nichols, Michael C.  2011.  Methods and equations for estimating aboveground volume, biomass, and carbon for trees in the U.S. forest inventory, 2010.  Gen. Tech. Rep. NRS-88. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 30 p.

Resource Materials for Projects in All Locations

Resources for Offset Project Operators

Resources for Verifiers

References for U.S. Forest Protocol




Download Free Microsoft Excel Viewer (.xlsx extension)

Download Free Quantum GIS (QGIS)

Download Explorer GIS (Coming soon!)



For questions or comments regarding the U.S. Forest Protocol please contact

Barbara Bamberger at 916-324-2303 or e-mail bbamberg@arb.ca.gov.

preload