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April 11, 2013
In Reply Refer To:
1731(220, 210) P
Instruction Memorandum 2013-111
Expires: 9/30/2014
To:                   State Directors
From:               Assistant Director, Lands and Renewable Resources
Subject:           The National Vegetation Classification and Associated Mapping Standards for Bureau of Land Management Planning Documents and Assignment of State-level Vegetation Classification Data Stewards                   DD: 05/01/2013
Program Area: Integrated Vegetation Management,Resource Management Planning
Purpose: This Instruction Memorandum (IM) provides policy guidance for describing vegetation at a given location at the time of observation (existing vegetation) at various landscape scales. It outlines consistent existing vegetation classification and mapping for all Bureau of Land Management (BLM) planning and assessment documents. The purposes of this policy guidance are:
  1. It provides a standardized, hierarchical classification system for existing vegetation consistent with the 2008 National Vegetation Classification Standard (NVCS) (See http://www.fgdc.gov/standards/projects/FGDC-standards-projects/vegetation) and the United Stated Federal Geographic Data Committee (FGDC) Vegetation Subcommittee. More information on the FGDC Vegetation Subcommittee is provided in Attachment 1.
  2. It defines terms and adopts standards for vegetated and non-vegetated (land cover) classification and mapping.
  3. It provides a consistent way of describing existing vegetation and desired future conditions.
  4. It provides a standard baseline to use in determining effects of climate change on vegetation and provides a coarse filter for multiple species habitat management.
  5. It facilitates collaboration and product consistency important for aggregating multi-scale vegetation data from local planning units to regional and national scales.
  6. It facilitates communication and data sharing of vegetation information between BLM administrative units.
  7. It ensures that the BLM complies with the FGDC core data requirements for vegetation classification and mapping.
This policy applies to classifying and mapping existing vegetation as well as other existing non-vegetated land cover (refer to Attachment 2 – Glossary for definitions). It does not apply to classification or mapping of potential vegetation or vegetation community conditions for various resources. Existing vegetation data using this classification system provides baseline information onto which other spatial data layers (e.g., potential vegetation, age classes, fuels condition classes) can be added to assist in developing land management objectives.
In addition to a standard vegetation classification system, mapping standards are needed to promote consistency between BLM administrative units. These standards will assist with data sharing, landscape assessments, cumulative impact assessments, and other analyses (e.g., habitat fragmentation, fuels continuity) that include a landscape approach.


The National Vegetation Classification Standard: This classification standard will be used by all states, districts, field offices and centers for all vegetation classification and mapping-planning purposes that require information on existing vegetation. The tables in Attachment 3 illustrate the classification system with examples. 

Resource Management Plans and Other Mid-scale Applications: The NVCS will be used for mid-scale assessments and planning documents to describe existing vegetation including all resource management plans (RMP) and plan amendments, national or regional level environmental impact statements (EIS), and ecoregional assessments. The macrogroup level will be used for RMPs because it provides the level of detail needed to distinguish plant communities at regional and sub-regional levels and it most easily crosswalks to Ecological Systems. The Landscape Fire and Resource Management Tools Project (LANDFIRE) currently uses Ecological Systems and has been involved in the development of a crosswalk from Ecological Systems to the NVC macrogroups (Attachment 4). Most planning units get their vegetation information from LANDFIRE. Depending on the scale of other projects, the three mid-levels of the classification (division, macrogroup and group) will be used. It may be preferable for national-level EIS projects to use divisions, and smaller scale projects may want to map to group (See tab 1 of Attachment 3). 

Use of the NVCS for RMP Analyses and Discussions: Effective immediately, state, district and field offices will use the NVCS for all new RMP and RMP amendment planning starts. The current BLM Planning Handbook (H-1601-1) requires that the BLM “identify desired outcomes for vegetative resources, including the desired mix of vegetative types, structural stages, and landscape and riparian functions; and provide for native plant, fish, and wildlife habitats and livestock forage”. It does not define what it means by vegetative type and plans have not consistently described or mapped vegetation types. The current handbook lists several sources to use for establishing desired outcomes for vegetation but does not provide a consistent way to map or describe existing vegetation units. Through this IM, we are defining “vegetative type” for planning purposes, as the macrogroup level of the United States National Vegetation Classification.  Additional plant community information such as age classes, fuel condition classes, and habitat condition, as well as ecological sites can be added as separate data layers.
The following items outline the policy guidance concerning the classification system and mapping for RMPs:
1.  The ‘general existing vegetation map’ in the RMP document will use the mid-scale macrogroup level of the NVCS as map units and those units will contain the macrogroup code from the classification. States can develop map units that aggregate to macrogroups as long as those map units crosswalk to the NVCS macrogroups. In some cases creating non-native macrogroup-level cover types and map units may also be necessary (see Idaho example in Attachment 3 – Table 2). 

2.  Discussion in the RMP dealing with existing vegetation (including maps) will use macrogroups and can use land cover units provided in the attached glossary. Descriptions can include the lower level classification units within the Macrogroups. The number of acres of each Macrogroup in the planning area and its relative importance should be discussed. Any land cover map units used will be listed in the glossary for the RMP.

3.  Additional analyses and discussions of important vegetation communities of finer thematic scale (NVC groups, alliances or associations) may be warranted to address issues for an RMP (e.g., aspen communities, riparian shrublands, wetlands, priority sage-grouse habitats). Display these finer-scaled communities in additional maps.

4.  Statistical information concerning existing vegetation will be limited to land cover within the RMP area boundary (see also 5.d. under General Mapping Standards).

5.  General Mapping Standards: The following are mapping standards for the ‘general existing vegetation map’ in the RMP:
a.  The minimum map units are: uplands = 2 ha (4.94 acres); riparian areas = 0.5 ha (1.23 acres or a 90 meter band along stream feature). 
b.  Extend land cover mapping at least 1.6 km (1 mile) and preferably 8 km (5 miles) beyond the RMP-area borders. 
c.  Map existing land cover for all lands within the above area including private, state or other Federal lands.

 6.  An accuracy assessment for the RMP ‘general existing vegetation map’ must be completed (see further guidance below). A description of methods used and mapping accuracy estimates associated with each classification strata must be in an appendix of the RMP. Any vegetation maps generated must contain an estimated accuracy statement for the vegetation on the BLM public lands displayed. 

Watershed or Project-Level Applications: The NVCS should be used or cross-walked and referenced for all fine-scale assessments and project-level planning documents to describe existing vegetation. Depending on the size of the project, the three lower levels of the classification (group, alliance, association) should be used or referenced. 
Regional and National Applications: The NVCS will be used for all national and regional assessments and broad-scale planning documents to describe existing vegetation. Use of the NVC should be written into all federally-funded contracts and agreements for any of these documents that have descriptions of existing vegetation. The macrogroup levels should be most commonly used in these documents. In the future, aggregated mid-scale data from RMPs and other sources will be a source of information for regional assessments and may be used for national or regional reporting or mapping.

Accuracy Assessments: Accuracy assessments are standard procedures for mapping existing vegetation and require technical expertise. Guidance is provided in Attachment 5. A description of methods used and mapping accuracy estimates associated with each classification strata should be completed for vegetation mapping projects. Mid-scale planning documents should follow guidance outlined for RMPs. Field offices can request guidance concerning accuracy assessments by contacting the National Operations Center (NOC) Geographer (mbobo@blm.gov) or State Office GIS coordinators. The Assessment, Inventory and Monitoring (AIM) Strategy Landscape Monitoring Framework Project with the Natural Resources Conservation Service is working with LANDFIRE to provide current vegetation data to supplement accuracy assessments.

Data Stewards: Each state and center will assign a data steward with responsibilities for the records and maps associated with vegetation classification and mapping as described in this IM. An understanding of plant systematics is required. Assigning data stewardship responsibilities to ecologists or botanists with plant systematics education and experience is recommended. The names of those assigned these data steward responsibilities will be sent to the Washington Office (WO) Deputy Division Chief, WO-220 by May 1, 2013 for continued coordination and implementation of this IM.

Timeframe: This policy is effective immediately. 

Background: Vegetation management on public lands faces increasingly complex and widespread challenges that transcend traditional administrative boundaries. There have been substantial vegetation changes in the last thirty years in the Western United States due to wildfire, weeds, insect outbreaks, energy development, urban growth and increased recreational use.  There is a significant need for a common vegetation classification language and mapping standards when describing existing vegetation and desired future conditions. This is true within the BLM between field offices, and for the BLM and other agencies working together across watersheds or landscapes.

Consistent, standardized classification and mapping of existing land cover was identified as a national need with the Federal Geospatial Data Committee (FGDC). All Federal agencies are expected to meet the core data requirements of the FGDC adopted National Vegetation Classification (http://usnvc.org/explore-classification/) when classifying existing vegetation and land cover. This classification is consistent with ongoing national and regional vegetation and land cover mapping efforts such as LANDFIRE, Northwest ReGap and Southwest ReGap. With the use of this classification system, the BLM meets these core data requirements. 

Rapid Ecoregional Assessments have shown a need for more accurate and consistent vegetation maps across the West. In the past, state and field offices have used different land cover and vegetation terminology and mapping standards; thus making communication and aggregation of data between administrative units difficult, and in many cases, impossible. Using standard procedures for describing and mapping existing vegetation will improve the BLM’s ability to make resource decisions and allocations, complete cumulative impact analyses, and monitor and implement adaptive management at multiple scales as outlined in the BLM’s Assessment, Inventory and Monitoring (AIM) Strategy.

Manual/Handbook Sections Affected: H-1601-1 Planning Handbook (Appendix C), H-1740-2 Integrated Vegetation Management Handbook.

Coordination: An Interdisciplinary BLM team (representatives from WO-220, 210, 200, Idaho 930 and the NOC) developed policy direction. The draft IM was reviewed informally sent to Deputy State Directors in October 2012 and was reviewed by State Offices, all of the Divisions in WO-200, WO-300 and WO-400 as well as the NOC, the National Interagency Fire Center, and the LANDFIRE Coordinator at the Department of the Interior. The adoption of this policy was discussed with the Multi-Resolution Land Characteristics Consortium and the FGDC Vegetation Subcommittee. Use of the NVCS was discussed in the development of ecoregional direction associated with applying information from rapid ecoregional assessments into planning documents as well as with vegetation mapping leads at several state offices.

Contacts: Lynda Boody; Division Chief; Forest, Rangeland, Riparian and Plant Conservation Division, 202-912-7222, or Carol Spurrier, Rangeland Ecologist, 202-912-7272 in the WO.

Signed by:                                                                   Authenticated by:
Edwin L. Roberson                                                      Ambyr Fowler
Assistant Director                                                       Division of IRM Governance, WO-560
Renewable Resources and Planning
6 Attachments
            2-Glossary of Terms (7 pp)

Last updated: 05-01-2013