Kelly Reeve: It’s a hot August morning on a remote mesa top in Mesa Verde National Park. And six National Park Service botanists are getting ready to catalog the ancient trees in this small plot of forest. [Sound of walking through forest Female voice: To be a tree, it has to be at least 15, centimeters, so... ] KR: These pinyon pine and juniper trees may be as old as the pottery shards that we find littered on the ground. Their rough branches and gnarled trunks keep getting in the way as the botanists draw out 50 meters of measuring tape to mark the plot. [Female voice: We'll do transect "C" first... ] Megan Swan: I think that you have some plots that are, favorites, some that are kind of nemeses [laughs] KR: That’s Megan Swan. She’s the head botanist for the crew. She has been returning to measure the plants and soils in the same plots, every year. [Sound of hammering Female voice: ...the pinyons, it's best if he nails it first, and then you measure directly blow, below or above... ] KR: In each plot, the crew spends three to six hours tagging and measuring the diameters of the trees and the amount of tree canopy; identifying the understory plants and estimating their extent; measuring the amount of bare soil; and testing how well the soil can resist erosion. MS: It’s really an extensive amount of information that we’re getting and then we can put that information together to get sort of an overall picture of what’s going on on the landscape. KR: Megan and the rest of the crew sample 110 to 140 plots in nine national parks on the Southern Colorado Plateau every year. The idea is to use the data they collect to track the health of upland ecosystems over the entire region, over a really long period of time. MS: Yeah, 50 or, 75 years from now, I’d love it if, you know, this project was still ongoing and doing well, and [pause] I certainly wouldn't be here to see it. I mean, hopefully it will go on for a long time, and I think that the longer it goes, the more good information that we’ll get out it. KR: George San Miguel is the natural resource manager for Mesa Verde National Park. He has a particular love of the pinyon-juniper woodlands in the park. George San Miguel: At Mesa Verde, in areas where there hasn’t been any disturbance, such as a fire, or a road access, or some other kind of development, they remain very much pristine. You can walk through the old growth pinyon-juniper woodlands and not find any weeds or any strange oddities in them. They’re very old, and so you’ll come across these great big trunk trees, that really stand out on the landscape. KR: These old growth pinyon-juniper trees may have been alive while the ancestral Puebloan people were living in the cliff dwellings. But, the park has only recently begun to really systematically study, and manage, the woodlands. GS: When people think of Mesa Verde, or they see a photograph of it, they think of the pinyon-juniper woodland as the natural backdrop to the world famous cliff dwellings. But Congress, in its wisdom, in establishing Mesa Verde, also said that one of the purposes for the park was “the preservation from injury or spoliation of all timber, natural curiosities, or wonderful objects within the park and for the protection of the animals and birds". And so, there you have it - one of the purposes of the park is preservation of the timber, which is of course an old expression for the woodlands. KR: George is worried about the pinyon-juniper woodlands. Only small areas of old-growth pinyon-juniper exist in the west. And unlike other trees out west, pinyons and junipers are easily killed by fire. And fire has been increasing across the west. Pinyon pines are also sensitive to drought - they just can’t survive without enough water. GS: ...and the early part of this decade was extremely, excruciating to witness. We suffered the worst drought in recorded history during the early part of this decade. We are definitely showing that, with a warming climate, we saw a big die-off of pinyon trees, which are a very important part of the ecology of the park. Changing climates means more disturbances, whether they are minor disturbances, or major disturbances, like a wild fire, all of those kinds of things in combination are leading to a very altered environment. That means that the communities are not recognizable in some places... KR: One of the first steps in protecting pinyon-juniper woodlands is to measure all the changes to the plants and soils that are occurring over time. Megan and her crew are doing this now. If they find a problem, park managers, like George San Miguel, can try to find solutions to heal the damage. MS: Well, the purpose of our program is to provide good scientific data to park managers. So, in that case, we’ll be presenting that information to the relevant natural resource managers in the parks, and they’ll be able to use that data to decide the course of action that they want to take, individually, and also region-wide. KR: The inventory and monitoring program that Megan Swan is a part of doesn’t just monitor plants and soils. They also keep track of other signs of ecosystem health, like birds, water quality, aquatic macroinvertebrates, and springs. And this effort isn’t just taking place over the Southern Colorado Plateau. It is part of a nation-wide effort across all national parks to systematically inventory and monitor important natural resources in the parks for decades to come. [Sound of crew working in the woodland, sound of hammering] KR: For the crews on the ground collecting all this data, that means that they get to visit the same spots every year. MS: And yeah, I think that, we get to go to a lot of neat areas in the parks that the average person doesn’t get to go to, and so it is sort of neat to be doing these same backcountry hikes year after year. You do kind of feel at home, I think. KR: And like in any home, the crew has to monitor the plants and soils, for wear and tear over time, so that the parks can protect them for the future.