National Wetland Plant List

AGENCY:

U.S. Army Corps of Engineers, DoD.

ACTION:

Notice.

SUMMARY:

The National Wetland Plant List (NWPL) provides plant species indicator status ratings, which are used in determining whether the hydrophytic vegetation factor is met when conducting wetland delineations under the Clean Water Act and wetland determinations under the Wetland Conservation Provisions of the Food Security Act. Other applications of the NWPL include wetland restoration, establishment, and enhancement projects. To update the NWPL, U.S. Army Corps of Engineers (USACE), as part of an interagency effort with the U.S. Environmental Protection Agency (EPA), the U.S. Fish and Wildlife Service (FWS) and the U.S. Department of Agriculture Natural Resources Conservation Service (NRCS), is announcing the availability of the draft changes to the 2020 NWPL and its web address to solicit public comments. The public will now have the opportunity to comment on the proposed changes to wetland indicator status ratings for five plant species in select regions and the addition of 22 new plant species to the NWPL.

DATES:

Comments must be submitted on or before May 24, 2021.

ADDRESSES:

U.S. Army Corps of Engineers, Attn: CECW-CO-R, 441 G Street NW, Washington, DC 20314-1000.

FOR FURTHER INFORMATION CONTACT:

Brianne McGuffie, Headquarters, U.S. Army Corps of Engineers, Operations and Regulatory Community of Practice, Washington, DC 20314-1000, by phone at 202-761-4750 or by email at brianne.e.mcguffie@usace.army.mil.

SUPPLEMENTARY INFORMATION:

Background

USACE administers the NWPL for the United States (U.S.) and its territories. Responsibility for the NWPL was transferred to USACE from the FWS in 2006. The NWPL has undergone several revisions since its inception in 1988. Additions or deletions to the NWPL represent new records, range extensions, nomenclatural and taxonomic changes, and newly proposed species. The latest review process began in 2020 and included review by Regional Panels (RPs) and the National Panel (NP).

Wetland Indicator Status Ratings

On the NWPL, there are five categories of wetland indicator status ratings, used to indicate a plant's likelihood for occurrence in wetlands versus non-wetlands: Obligate Wetland (OBL), Facultative Wetland (FACW), Facultative (FAC), Facultative Upland (FACU), and Upland (UPL). These rating categories are defined by the NP as follows: OBL—almost always occur in wetlands; FACW—usually occur in wetlands, but may occur in non-wetlands; FAC—occur in wetlands and non-wetlands; FACU—usually occur in non-wetlands, but may occur in wetlands; UPL—almost always occur in non-wetlands. These category definitions are qualitative descriptions that better reflect the qualitative supporting information, rather than numeric frequency ranges. The percentage frequency categories used in the older definitions are only used for testing problematic or contested species being recommended for indicator status changes. Plus and minus designations and wetland indicator designations such as No Indicator (NI), No Occurrence (NO), and No Agreement (NA) were removed in 2012 and are no longer used on the NWPL. More information on the specifics of how to use these ratings is available on the NWPL website at http://wetland-plants.usace.army.mil/.

The NWPL is utilized in conducting wetland delineations under the authority of Section 404 of the Clean Water Act (33 U.S.C. 1344) and Section 10 of the Rivers and Harbors Act of 1899 (3 3 U.S.C. 401 et seq.) and wetland determinations under the authority of the Food Security Act of 1985 (16 U.S.C. 3801 et seq.). For the purposes of determining how often a species occurs in wetlands, wetlands are defined as either (1) those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions (33 CFR 328.3) or (2) “except when such term is part of the term `converted wetland,' means land that has a predominance of hydric soils; is inundated or saturated by surface or groundwater at a frequency and duration sufficient to support a prevalence of hydrophytic vegetation typically adapted for life in saturated soil conditions; and under normal circumstances does support a prevalence of such vegetation, except that this term does not include lands in Alaska identified as having a high potential for agricultural development and a predominance of permafrost soils.” (16 U.S.C. 3801(a)(27) and 7 CFR 12.2). Because each plant species being evaluated occurs as part of a vegetation assemblage, examining all species present in relation to their assigned wetland fidelity may be useful in assessing hydrophytic vegetation.

2020 Update Information

For the 2020 NWPL update, the NWPL NP and RPs reviewed proposed wetland rating changes or additions for 27 species and 48 regional ratings (some species were reviewed for multiple regions) submitted by the public. Twenty-two of these species were proposed for addition to the NWPL, and five species were submitted for a rating change request in one or more regions. Submitted information was reviewed by the NP and RPs, and proposed 2020 ratings for these species were determined, as detailed below. Note that all submitted species are included here, regardless of whether or not the NP and RPs proposed a rating change. Hence, for those species where a rating change request was submitted but review of the submitted information did not result in a rating change for the 2020 update, the current and proposed ratings are the same. In several cases, it was determined that a species recommended for addition did not occur within the region recommended (per USDA PLANTS). In these cases, no proposed species addition or indicator status was carried forward.

As part of the 2020 NWPL update, USACE is also proposing administrative changes to reformat the Hawai'i and Pacific Islands Region (HI) and the South Pacific Islands Subregion (SPI). NWPL subregions are areas in which small numbers of wetland plants have wetland indicator status ratings that differ from the ratings for the same plant species in the rest of the region. Boundaries of subregions are typically based on Major Land Resource Areas. Under the current format, the SPI includes certain plant species which have an indicator status rating for SPI but not for HI (see e.g., indicator status ratings for Abildgaardia ovata; SPI= FACW, HI= NL). This current format of HI/SPI is inconsistent with the formatting of other NWPL regions and subregions and has caused some confusion when applying the NWPL within HI. USACE proposes two administrative changes to reduce this confusion. Neither of the proposed administrative changes to SPI or HI will affect the current boundaries of SPI, HI, or any other NWPL regions or subregions.

USACE proposes to reformat SPI and HI by merging the lists of plant species from the existing SPI and HI to form a single, comprehensive region, with SPI serving as a subregion of HI, instead of the current state of the region in which SPI serves as a stand-alone subregion separate from the larger HI region. As proposed, plant species which currently have an indicator status rating for SPI but not for HI (e.g., Abildgaardia ovata) will now have a single, comprehensive indicator status rating for the entire region (HI). For those species which currently have differing indicator status ratings between SPI and HI (e.g., Abrus precatorius), the current indicator status rating for SPI will be added to the reformatted SPI, which, as proposed, will serve as a subset of indicator status ratings within HI and will include only those plant species and associated indicator status ratings which differ from the HI indicator status rating. With the exception of Xylocarpus moluccensis and Ligustrum lucidum, which were submitted by the public, USACE is not proposing any changes to wetland indicator status ratings for SPI or HI. All current indicator status ratings for SPI and HI will be retained through this proposed reformatting. As proposed, the USACE believes this administrative change will provide greater clarity for the public, remove redundancies in the NWPL that currently exist between SPI and HI, allow for a consistent formatting of subregions between all NWPL regions, and more accurately and appropriately reflect species' distribution and wetland frequency within SPI and HI.

USACE is also proposing to rename SPI from its current name, “South Pacific Islands Subregion”, to “Pacific Islands Subregion.” This subregion includes islands which are located within both the northern Pacific (i.e., the Commonwealth of the Northern Mariana Islands and the Territory of Guam) and southern Pacific (i.e., the Territory of American Samoa). Therefore, the proposed name change will more accurately characterize the geographic extent and spatial variability of this subregion. The proposed change also creates consistency between the naming conventions of the NWPL regions and subregions and the Regional Supplements to the Corps of Engineers Wetland Delineation Manual regions.

Instructions for Providing Comments Online

USACE encourages public input in the form of data, comments, literature references, or field experiences, to help clarify the status of the species reviewed for this update. The list of these same 27 reviewed species, and their draft 2020 wetland ratings by region, can be viewed at the NWPL homepage, http://wetland-plants.usace.army.mil/ under “2020 NWPL Update Information.” A link to provide general or species-specific comments in response to this notice is also available at this location. Users are encouraged to submit literature citations, herbaria records, experiential references, monitoring data, and other relevant information. Specific knowledge of, or studies related to, individual species are particularly helpful. When providing input or information on the draft changes to the 2020 NWPL update, commenters should use their regional botanical and ecological expertise, field observations, reviews of the most recent indicator status information, appropriate botanical literature, floras, herbarium specimens with notation of habitat and associated species, habit data, relevant studies, and historic list information. Providing ratings without supporting documentation or information is not recommended. All submitted comments and information will be compiled and sent to the National Panel for their review and consideration.

USACE is also seeking comments on the NWPL update process. Detailed information on the update process, protocol, and technical issues can be found in the following documents, which are available on the “NWPL Publications” web page:

• Lichvar, Robert W. and Minkin, Paul. Concepts and Procedures for Updating the National Wetland Plant List. Sept 2008. ERDC/CRREL TN-08-3. Hanover, NH: U.S. Army Engineer Research and Development Center, Cold Regions Research and Engineering Laboratory.
• Lichvar, Robert W. and Gillrich, Jennifer J. Final Protocol for Assigning Wetland Indicator Status Ratings during National Wetland Plant List Update. Sept 2011. ERDC/CRREL TN-11-1. Hanover, NH: U.S. Army Engineer Research and Development Center, Cold Regions Research and Engineering Laboratory.
• Lichvar R.W., N.C. Melvin, M.L. Butterwick, and W.N. Kirchner. 2012. National Wetland Plant List Indicator Rating Definitions. ERDC/CRREL TN-12-1. Hanover, NH: U.S. Army Engineer Research and Development Center Cold Regions Research and Engineering Laboratory.

Future Actions

Future updates to the NWPL will occur biennially. A change in indicator status for a given species, or a proposed species addition may be requested at any time at http://wetland-plants.usace.army.mil/ under “Submit NWPL Change Request.” Submissions throughout the two-year period will be compiled and reviewed prior to each NWPL update and any resulting proposed changes will be reflected in the subsequent notice of an updated list.