Study helps reverse the trampling effects in Glacier National Park

During 1967, a young doctoral student wondered what effect visitors were having on the delicate grasses and flowers at Logan Pass, and how long it might take for the landscape to recover.

The one-of-a-kind study that ensued is still alive 38 years later, and Dr. Ernest Hartley is still at the helm. His work has led to significant changes at Logan Pass, most notably, construction of a boardwalk leading to the Hidden Lake Overlook, along with policies and signs that discourage people from leaving established trails.

That's not how it always was. Back when Hartley first arrived at Logan Pass as an undergraduate student at the University of Montana, and as a graduate student from Duke University in 1967, there were no restrictions on visitors.

It was a hiker free-for-all, with trails snaking out in all directions from a scar-like trail leading to Hidden Lake.

In a slide presentation this week at the Glacier's community center, Hartley shows off an old promotional brochure that says, "When you leave the park, take nothing but photographs and leave nothing but footprints."

"I found that indeed people were leaving footprints all over the place," said Hartley, a former teacher who worked for years as director of the Towe Ford Museum in Red Lodge.

A 1957 aerial photograph shows the extent of the ad hoc trails.

"These informal trails were created by visitors who just wanted to have a better look," says Hartley, who is now 66 and living in California's Sacramento area. "It was basically people walking where they wanted to."

Hartley recalls how it was common for folks to lay out blankets and have picnics among the wildflowers. Nobody recognized it at the time, but that kind of use had impacts.

"You step on a glacier lily this year, and it won't flower next year," is Hartley's most basic message. "People need to know these things when they go into a severe environment."

And Logan Pass is indeed a "severe" environment, where plant life must be highly opportunistic to survive moisture-sapping winds, extreme cold, nutrient deficient soils and snow depths that lead to an extremely short growing season.

What sets Hartley's work apart from other studies is the period of time it has spanned, along with the numeric data he has collected by counting plants within established plots on Logan Pass..

"This is a seminal study," said Dan Fagre, a U.S. Geological Survey scientist who has done considerable research on the effects of climate change and vegetation in Glacier. "There are virtually no others like it."

Fagre noted that the study provides information on how long it takes for certain plant species to recover after varying amounts of trampling.

"Mine was the first quantitative study," Hartley said, explaining that similar impact studies have been "qualitative" projects involving observations, and most of those spanned less than a few years. Quantitative translates to tens of thousands of plant counts within the plots, numbers that have been crunched into statistical sense by Hartley's partner, Susan Fredericks.

One part of the study measured impacts on trailside vegetation, while another part established "trampling treatment" plots on Caribou Ridge, for the purpose of evaluating known quantities of trampling.

In one grid, for instance, Hartley and his assistants would trample the vegetation 15 times a week, and in another they would trample 50 times in a week. The first year showed significant immediate impacts.

In the plot with the heaviest impact in 1967, the vegetation cover decreased from 77 percent to 11 percent, while bare ground increased from 3 percent to 45 percent.

During the periodic years when he monitored the plots, Hartley was able to measure rates of recovery.

Recovery required 5 to 10 years longer in the plots trampled 50 times than in those receiving only 15 trampling treatments. Depending on plant species involved, some plots with the heaviest impacts took 30 years to return to pre-treatment measurements of vegetation.

Hartley's study concludes that "the greater the impact of trampling, the greater number of years required to return to normalcy." And his work found that different plants have varying rates of recovery.

The trail-side portion of the study monitored the manner in which trails tend to widen over time.

"People will courteously step aside to let other people pass. Everybody's seen that. But over time, it has an effect."

Trail-side trampling impacts were shown to be greatest within three meters of a trail, and Hartley's study found that plant communities vary widely from trailside to just a few meters away.

Hartley's says the study has been worth the time and effort, largely because it has provided useful information to park managers.

"Scientific research is essential to the proper management of just about anything," Hartley said.

"It's important because the ecosystems in the national parks are supposed to be kept 'unimpaired' for people's enjoyment," Hartley said, referring to the Organic Act of 1916, which established the National Park Service's basic mission.

It's a seemingly conflicting situation: visitors are routed to Logan Pass - one of Glacier's most ecologically sensitive areas - more than any other place in the park. It's a situation that demands management, and Hartley says park officials have increasingly dedicated themselves to protecting Logan Pass while maintaining its accessibility.

"They do it because it's so beautiful and people enjoy it," Hartley says.

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com