National Park Service

Northeast Temperate Network (NETN)

Parks in this Network

NETN Network Map
Click to see Larger
Network Map
Find your park logo

Appalachian National Scenic Trail

Fall colors cover the forest below the vantage point from Annapolis Rock along the A.T. in Maryland Fall colors cover the forest below the vantage point from Annapolis Rock along the A.T. in Maryland. NPS photo.
NPS LogoAppalachian NST Website
A.T. Study Permitting Requirements
APPA map
Appalachian NST map. Click for full trail map.

The Appalachian National Scenic Trail traverses more than 2,170 miles across the highest ridgelines of the Appalachian Mountains, from Georgia to Maine, in a southwest to northeast gradient. In its traverse, the Trail, which is a unit of the National Park System, crosses through 14 states, eight National Forests, six other units of the National Park System, one National Wildlife Refuge, three Tennessee Valley Authority properties, one Smithsonian Institute property, and 287 local jurisdictions. The Trail is managed in partnership with the Appalachian Trail Conservancy (ATC) and its 30 affiliated Trail-maintaining clubs under an extraordinary cooperative management system that provides for an annual contribution of nearly 200,000 hours by more than 5,000 volunteers. The Appalachian Trail passes through six Inventory and Monitoring Program networks, with the Northeast Temperate Network taking the administrative lead:

  • Appalachian Highlands (APHN)
  • Cumberland-Piedmont (CUPN)
  • Eastern Rivers and Mountains (ERMN)
  • Mid-Atlantic (MIDN)
  • National Capital (NCRN)
  • Northeast Temperate Network (NETN)

The trail's length, north-south alignment, changes in elevation, and numerous peaks and ridges it crosses along this ancient mountain chain creates one of the most biodiverse units of the National Park System.

The Appalachian Trail is uniquely situated to serve as a barometer for the air, water, and biological diversity of the Appalachian Mountains and much of the eastern United States. That is what makes the A.T. an attractive place to explore scientific questions, and which lead to the creation of the A.T. MEGA-Transect. To this end, the National Park Service and ATC, in cooperation with the USDA Forest Service, the U.S. Geological Survey, and a host of other agencies and organizations, are focusing their energies on assessing, understanding, and monitoring the vast wealth of natural resources present on the Appalachian Trail’s 270,000-acre land base.

The A.T. MEGA-Transect is built around four fundamental goals:

  • Monitor-- Collect and synthesize existing and new data on key indicators of environmental health from agencies, organizations, researchers, and citizen scientists
  • Understand-- Transform status and trend data into knowledge through analysis, synthesis, and modeling
  • Inform-- Provide early warning of undesirable conditions or trends, such as climate change, as a means of better protecting the resources and reducing costs of management
  • Engage-- Share knowledge by engaging, educating, and involving decision makers, stakeholder organizations, and citizens

Anticipated uses of monitoring results:

  • Adaptive Management and Science - Provide sound scientific baseline and trend information about environmental conditions on the Appalachian Trail to help inform practice and science
  • Public Policy and Action - Utilize large-scale data sets to inform the public and influence decisions
  • Public Engagement and Education - Involve citizens and use the Appalachian Trail’s iconic status to convey key findings to the public.

Long-term Objectives:

  • Establish the Trail as the continent's first environmental monitoring "Mega-Transect"
  • Advance the state of scientific knowledge of issues affecting human health and the environment
  • Communicate results through scientific and popularly accessible publications
  • Encourage participation by researchers, agencies and citizen scientists.

The Appalachian Trail is monitored through NETN's Vital Sign Monitoring Program. The goals of monitoring along the trail include:

  • Determine the status and trends in selected indicators of the condition of park ecosystems to allow managers to make better-informed decisions and to work more effectively with other agencies and individuals for the benefit of park resources
  • Provide early warning of abnormal conditions of selected resources to help develop effective mitigation measures and reduce costs of management
  • Provide data to better understand the dynamic nature and condition of park ecosystems and to provide reference points for comparisons with other, altered environments
  • Provide data to meet certain legal and Congressional mandates related to natural resource protection and visitor enjoyment
  • Provide a means of measuring progress towards performance goals

Because most protocols address multiple vital signs, the NETN program is organized around protocols, rather than vital signs. The table below shows monitoring and inventory activity for the Appalachian Trail, and the relationship between NETN monitoring protocols and inventories to vital signs.The table also provides links for reports, vitals signs pages, and outreach materials.

Monitoring Programs Vital Signs Addressed Protocols & Annual Reports Outreach Products
Air Quality Acidic Deposition & stress,contaminants,and ozone.




Breeding Landbirds Breeding Landbirds

Mountain Birdwatch Protocol


Mountain Birdwatch website


Long-term Forest Health Forest Vegetation, Forest Soil, Invasive/Exotic Plants, Invasive/Exotic Animals, Ozone, Land Cover, White-tailed Deer, Atmospheric Deposition & Stress

Annual Reports


Resource Briefs

Program Brief

Phenology Phenology Protocol Development Summary

Resource Briefs

Program Briefs

Rare Plants Rare Plants  


Monitoring Programs in Development Vital Signs Addressed Protocol Development Outreach Products
Weather and Climate Climate Protocol Development Summary

Resource Briefs


Inventories Vital Signs Addressed Reports Outreach Products
Inventory of Terrestrial Mammals   Collection on IRMA  
Vegetation Classification and Mapping   In Progress. 2005-2015 Vegetation Mapping for the A.T. info
Land   Land Cover Change (2009)  
Baseline Inventories Complete for Park? Reports, Documents & Data Outreach Products
Water Quality Y Baseline Inventory Level-1 Water Resources Inventory

Base Cartography

Y Base Cartography Data Inventory (2001 - 2010)  
Air Quality Related Values Y (Note that N deposition report includes APPA in APHN; acid deposition report has APPA in NETN.) Air Quality Monitoring in NETN Parks  
Climate Inventory Y Weather and Climate Inventory for NETN parks (2006)  
Geological Resources Inventory Planned


Soil Resources Inventory Not scheduled    
Water Body Location and Classification N    
Vegetation Inventory In progress; expected 2016  
Species Lists Y IRMA Species Search  
Species Occurrence and Distribution Y Biological Resources Search on IRMA  

Other A.T. Materials and Data:

Posters & Presentations


The Appalachian Trail MEGA-Transect, Ramapo, NJ [Powerpoint]
The Appalachian Trail MEGA-Transect -- Organization for Fish and Wildlife Information Managers, Shepardstown, WV [Powerpoint]
The Appalachian Trail Environmental Monitoring Initiative and National Biological Information Infrastructure NBII) -- Inventory and Monitoring Program Data Managers Conference, Ft. Collins, Co. [Powerpoint]
A.T. MEGA-Transect: Appalachian Trail Environmental Monitoring Program -- Southern Appalachian Man and the Biosphere Conference, Johnson City, Tn. [Powerpoint]
The Appalachian Trail MEGA-Transect -- Northeast Region Natural Resource Managers Conference, Shepardstown, WV. [PDF]


Appalachian Trail MEGA-Transect: An Introduction -- George Wright Society, Portland, Or. [PDF]


Rare Plants and Exemplary Communities Train-the-Trainer Workshop, Shepardstown, WV. [Powerpoint]
A.T. MEGA-Transect -- DOI Leadership Briefing, Philadelphia, Pa. [Powerpoint]
MEGA-Transect Update -- A.T. Festival, Castleton, Vt. [Powerpoint]
Rare Plants and Exemplary Communities Update -- A.T. Festival, Castleton, Vt. [Powerpoint]


Department of the Interior Conference on the Environment, Portland, Or. [PDF]
Appalachian Trail Decision Analysis Workshop, Harpers Ferry, WV.
Existing Process [Powerpoint]
Selection of Forest Segments [Powerpoint]
Sampling Schemes [Powerpoint]
Ecological Society of America, Pittsburgh, Pa. [Powerpoint]
Decision Support System Project Meeting, Kingston, RI [Powerpoint]


Appalachian Trail Stewardship Council Meeting, Shepardstown, WV. [Powerpoint]
Virginia Journeys: Appalachian Trail Biennial Meeting, Emory & Henry College, Emory, Va. [Powerpoint]

Spatial Data

Appalachian Trail GIS File List (pdf)
Appalachian Trail GIS Sampling Pack (Large File -- 191 MB)
Download Metadata ONLY!
Appalachian Trail GIS Base Files (Large File -- 68 MB)
Download Metadata ONLY!


⇑ To Top of Page

Last Updated: December 30, 2016 Contact Webmaster