High visitation has taken a toll on the unique and fragile alpine ecosystem atop the Northeast’s highest peak, where erosion, trampling, and invasive species are challenging the ability of native plants to thrive.
That’s one finding of a preliminary summit assessment, prepared by consulting firm Tighe & Bond, that outlines the condition of the natural and built environment atop the 6,288-foot mountain. It’s one of the most in-depth studies of the immediate area that’s ever been undertaken, according to Mount Washington State Park Manager Patrick Hummel.
The new understanding of the summit environment contained in the report, he said, will inform discussions about how to make Mount Washington’s built infrastructure more welcoming and resilient while also protecting surrounding wildlife.
“I view this as a very important and thorough snapshot in time,” Hummel said.
The summit assessment originated with the 2022 Mount Washington Master Plan, which called for a third-party report assessing the facilities and environmental conditions at and around the mountain’s summit.
In November, Tighe & Bond presented a preliminary summary of the assessment before the Mount Washington Commission, which advises the Department of Natural and Cultural Resources on summit management.
In addition to evaluating the impact of high foot traffic on sensitive alpine species, the presentation pointed to gaps in knowledge about possible chemical contamination legacies at the sites of former buildings on the summit, proposed safety and durability improvements for existing buildings, and suggested ways to improve visitor and staff experiences while protecting the integrity of the mountain itself.
Once the report is finalized, expected by the end of this year, “it will be up to our mountain community and summit partners to really talk about what the future of the summit looks like, and how we get there,” Hummel said.
Crowds imperil rare plants
The ecosystem found on Mount Washington’s summit, called northern Appalachian alpine tundra, is rare in the United States, existing only at high elevations in a few Northeastern states. It is home to rare and endangered plants and animals, some of which, like the White Mountain fritillary, are not found outside the White Mountains region.
But invasive species, erosion, trampling, and climate change-driven shifts in weather patterns are limiting the success of native plant communities and wildlife at the summit, according to the presentation.
Assisted by the Department of Natural and Cultural Resource’s Natural Heritage Bureau, the consultants catalogued and documented plant and animal species found at the summit. The group also used wildlife cameras and assessed the impacts of climate stress on the summit, using the findings to generate an “ecological integrity” score for different zones of the park.
Eight zones around the summit itself received a grade of B-minus, while the area along the highest portion of the Mount Washington Auto Road scored C-plus and the summit itself, including the area immediately surrounding the buildings, received a score of C-minus.
Factors in these scores included a high prevalence of invasive plant species, according to the report. About 1 in 5 plant species the group identified within the entire state park area were non-native. Invasive plants can out-compete and encroach on native species, about half of which found on the summit are considered critically imperiled or vulnerable, according to the report.
Causing unwitting harm
The report linked the presence of non-native plants to that of human visitors, describing that non-native species are often brought to the summit on “vectors” including people and their vehicles. The consultants called for use of boot brushes, which can remove seeds from visitors’ shoes, and vehicle inspections to remove hitchhiking plants.
Visitors can also unwittingly harm native communities when they stray from marked trails, contributing to erosion and compaction of the already-limited patches of soil atop the mountain and crushing delicate alpine plants. These species are especially hardy to many types of mountaintop adversity, from the short growing season to extra ultraviolet radiation and harsh temperatures. But they also tend to grow slowly, and that makes it especially hard for them to overcome crushing and trampling, researchers have found.
This poses a challenge in an environment like Mount Washington’s summit, where rare and vulnerable plants coexist with the more than 250,000 visitors who pass through each year, according to an estimate by the Mount Washington Observatory.
“There is, to some extent, only so much room” on the summit, said Hummel. Trails are marked, and signs warn visitors not to stray off them. Yet, he said, “people tend to just wander. Naturally, you can’t keep everyone exactly where you want them.”
The administrative rules of the New Hampshire State Parks don’t explicitly forbid going off-trail, but the rules do prohibit damaging or disturbing natural structures and wildlife, and introducing any wildlife or object — both things that can happen when hikers stray from the path, according to the report. The report recommended that the park explore new ways to keep visitors corralled, including boardwalks, overlooks, railings, and additional educational signage.
Problems with built infrastructure
The assessment also identified issues with the infrastructure at the summit, including several buildings, stormwater and traffic infrastructure, and the pathways and platforms that visitors travel to explore the site.
These included needed maintenance at the largest building on the summit, which houses state park and Mount Washington Observatory staff, as well as visitor facilities. The building can become congested with growing crowds, according to the report. It also has some leaks and safety hazards, like uneven flooring, according to the presentation. From implementing self-checkout at the cafeteria to improving and clarifying egress routes, the report contains recommendations for improving conditions inside the building.
The presentation also outlined deficiencies in other summit structures, like the historic “Tip-Top House,” originally constructed in 1853, and the Yankee building, which houses communications equipment and is currently in “poor condition,” according to the report.
Fuel spills and chemical contamination also exist (or are thought to be possible, but yet unconfirmed) at different locations on the summit, according to the presentation. This includes debris from previous fires and coal dust that may be released along the Cog Railway.
One location about which information is lacking was once home to a U.S. Air Force research facility where military research on aircraft icing once took place, according to the presentation. Some known “potential hazards” remain on the site, including foundations and debris, but a full assessment of any chemicals and potential contaminants released during the facility’s operations is still incomplete.
Preserving a unique experience
Mount Washington’s extreme environment and high traffic exacerbate many of the challenges outlined in the assessment, Hummel acknowledged. But those realities are also what make the mountain so special, and Hummel wouldn’t have it any other way.
On a nice day, thousands of people may pass through the state park. For most of them, Hummel noted, the experience is highly anticipated and will become a lasting memory.
“People are wowed by the weather, wowed by the views,” he said. “… They’re able to come up and be wowed by the mountain and share that experience directly with state park staff, who are there because we love the place — and we get to share that excitement with one another.”
Though high volumes of visitors require attentive management, they also reflect the way that Mount Washington’s infrastructure makes the wonder of New Hampshire’s White Mountains accessible. The park draws visitors from far and wide: Hummel said visitors from 93 countries outside the U.S. and Canada had signed the park’s voluntary visitor log in 2025.
To Hummel, this is a sign that the state park is succeeding with one of its central goals.
“We are charged with … providing the access and the recreational opportunities and educational components and all of those things that link our lands to our visitors and our communities,” he said.
But overseeing such high visitation while also protecting a beloved landscape is a challenge, and the assessment shows that the summit ecosystem has borne some of that burden. Preserving the integrity of the peak while welcoming more visitors into the future, Hummel said, will take adaptation.
“The summit, obviously, is ever-evolving. It’s always changing,” he said.
New Hampshire Bulletin is part of States Newsroom, a nonprofit news network supported by grants and a coalition of donors as a 501c(3) public charity.