About AmeriFlux Core Sites

What are the AmeriFlux Core Sites?

AmeriFlux Core Sites are flux towers whose managing PIs and staff have agreed to deliver timely, high quality, continuous data to the AmeriFlux database. They receive operations and instrumentation support from the AmeriFlux Management Project (AMP).  A primary goal for AMP is to ensure high quality data collection from these sites, which represent a broad range of ecosystems and locations in the continental United States.  AMP receives funding support for the AmeriFlux core sites from Department of Energy, Office of Science, Terrestrial Ecosystem Science Program.

Currently 44 AMP-supported core sites exist, in 11 clusters, and 2 individual sites. Two more sites (US-MOz and US-ARM) have voluntarily agreed to the same data quality and delivery standards as the AMP-supported core sites, but do not receive AMP funding. The original sites were selected after careful review in 2012-2013, based on ecosystem representation, length of prior data record, quality of existing data, and established ability of site PIs to provide continuity in site management.

In our blog series Note from the Flux Site, Core site staff offer their own perspectives into various challenges and scientific questions that arise at their site.

Note: A Core Site Cluster is a case where support for one primary core site has been leveraged to support several sites. For example, support for a data manager assures timely data review and processing for several sites.

Santa Rita Mesquite - US-SRM

Santa Rita Mesquite – US-SRM. Credit Russ Scott, USDA-ARS.

Current Core Sites with Contacts

*Signifies this is the “primary” site for that core site cluster.

Harvard Forest

  • US-Ha1* • Harvard Forest EMS Tower (HFR1): deciduous broadleaf forest
  • US-Ha2 • Harvard Forest Hemlock Site: evergreen needleleaf forest: primarily hemlock

Bill Munger, Harvard University, jwmunger@seas.harvard.edu

Morgan Monroe State Forest (MMSF)

  • US-MMS* • Morgan Monroe State Forest: deciduous broadleaf forest

Kim Novick, Indiana University, knovick@indiana.edu
Rich Phillips, rpp6@indiana.edu

Note: US-BRG • Morgan Monroe State Forest retired late 2021.

ChEAS (Chequamegon Ecosystem-Atmosphere Study)

  • US-Los* • Lost Creek: shrubby wetland (longest running wetland flux site in US)
  • US-Syv • Sylvania Wilderness Area: old-growth (350 y) mature northern hardwood forest
  • US-PFa • Park Falls/WLEF (very tall tower): shrub/forest wetland, mixed conifer/hardwood (50 y)
  • US-WCr • Willow Creek (mature hardwood): mature northern hardwood forest
  • US-ALQ • Allequasch Creek: permanent wetland

Ankur Desai, University of Wisconsin, desai@aos.wisc.edu
Ken Davis, Pennsylvania State University, kjd10@psu.edu

New Mexico Elevation Gradient (NMEG)

  • US-Mpj* • Pinon-juniper site (Mountainair): pinyon-juniper forest 2100 m
  • US-Wjs • Juniper savanna site (Willard): open shrubland, 1925 m
  • US-Vcp • Valles Caldera National Preserve: evergreen needleleaf forest (Ponderosa pine), 2542 m
  • US-Vcm • Valles Caldera National Preserve: evergreen needleleaf (mixed conifer), 3000 m; wildfire in 2012
  • US-Ses • Sevilleta (LTER desert shrubland): open shrubland, 1593 m
  • US-Seg • Sevilleta (LTER desert grassland): desert grassland, 1622m
  • US-Vcs • Subalpine mixed conifer: evergreen needleleaf forest, 2752 m

Marcy Litvak, University of New Mexico, mlitvak@unm.edu

Santa Rita/Walnut Gulch

  • US-SRM* • Santa Rita Mesquite: semi-desert grassland
  • US-Wkg • Walnut Gulch Kendall Grasslands: desert grassland, grazing
  • US-Whs • Walnut Gulch Lucky Hills Shrub: Chihuahuan Desert shrubland
  • US-SRG • Santa Rita Grassland: semi-desert grassland

Russell Scott, USDA-ARS Western Area, Russ.Scott@ars.usda.gov


  • US-Ton* • Tonzi Ranch: Sierra Foothills—oak savanna, grazed
  • US-Var • Vaira Ranch • Ione: Sierra Foothills—oak savanna, grazed
  • US-Myb • Mayberry Wetland: Sacramento Delta—wetland restored 2010
  • US-Bi1 • Bouldin Island Alfalfa: croplands
  • US-Bi2 • Bouldin Island Corn: cropland

Former sites in this cluster:

  • US-Snd—Sherman Island. Retired 2015 as the land was converted into a restored wetland.
  • US-Twt—Twitchell Island. Sacramento Delta—rice paddy. Retired 2017.
  • US-Tw3—Twitchell Alfalfa. Retired 2018.
  • US-Tw1 • Twitchell Island (wet west): Sacramento Delta—wetland restored 1997. Retired 2023.
  • US-Tw4—Twitchell East End Wetland. Removed from Core site cluster in 2020 (still operational as of 4/2023).
  • US-Sne—Sherman Island Restored Wetland. Removed from Core site cluster in 2020 (still operational as of 4/2023).

Dennis Baldocchi, UC Berkeley, baldocchi@berkeley.edu

North Carolina Loblolly Pine  

  • US-NC2* • NC Loblolly Plantation: SE Loblolly Pine, managed
  • US-NC4 • Alligator River National Wildlife Refuge: coastal forested wetlands experiencing rising water level

Note: US-NC3—NC Loblolly: SE Loblolly Pine, managed. Retired late 2021, due to vegetation outgrowing infrastructure.

Asko Noormets, Texas A&M, noormets@tamu.edu
John King, North Carolina State University, john_king@ncsu.edu

Niwot Ridge

  • US-NR1* • Niwot Ridge Forest (LTER NWT1): subalpine conifer forest

Peter Blanken, University of Colorado, blanken@colorado.edu

University of Michigan Biological Station (UMBS)

  • US-UMB* • University of Michigan Biological Station: deciduous broadleaf forest
  • US-UMd* • UMBS Disturbance: deciduous broadleaf forest, succession experiment
  • US-OWC • Old Woman Creek: natural freshwater estuary
  • US-RRC • Rice Rivers Center Marsh: restored freshwater, tidal wetland

Gil Bohrer, Ohio State University, bohrer.17@osu.edu
Christopher Gough, Virginia Commonwealth University, cmgough@vcu.edu


  • US-Ro5* • Rosemount: corn/soybean rotation.  Replaces Ro1.  See Note.
  • US-Ro4 • Rosemount: restored prairie. New late 2015. Replaces Ro3.  See Note.
  • US-Ro6 • Rosemount: corn/soybean/winter cover rotation with minimal tillage. Replaces Ro2.  See Note.

Note:  Ro1-conventional corn/soybean rotation (no longer active).  The system was moved to a new field in 2017 (US-Ro5).
Note:  Ro2-Alternative agricultural site (no longer active).  The system was moved to a new field (US-Ro6).
Note: Ro3—corn/soybean in permanent kura clover. Retired late 2015. (US-Ro4)

Tim Griffis, University of Minnesota, tgriffis@umn.edu

Howland Forest

  • US-Ho1* • Howland Forest (main tower): since 1996
  • US-Ho2 • Howland Forest (west tower): since 1999
  • US-Ho3 • Howland Forest (harvest site): since 2003

Andrew Ouimette, USDA Forest Service Northern Area, Andrew.Ouimette@usda.gov

Metolius Pine

  • US-Me2* • Metolius-intermediate aged Ponderosa pine: evergreen needleleaf forest, 64 y
  • US-Me6 • Metolius young pine burn: evergreen needleleaf forest, 20 y, post-fire
  • US-Me4 • Metolius-old aged ponderosa pine (site reestablished in 2024)

Christopher Still, Oregon State University, Chris.Still@oregonstate.edu


  • US-Ne1* • Irrigated continuous maize
  • US-Ne2 • Irrigated maize/soybean, no-till
  • US-Ne3 • Rainfall maize/soybean, no-till

Andrew Suyker, University of Nebraska-Lincoln, asuyker@unl.edu

Former Core site cluster: Konza (Core site cluster from 2014-2020)

  • US-Kon • Konza Prairie LTER
  • US-KFS • Kansas Field Station
  • US-KFB • Konza Prairie LTER
  • US-KLS • Kansas Land Institute

Nate Brunsell, Kansas State University