When the Leonora Curtin Wetland Preserve opens again in the spring, visitors will find a very different landscape. A $20,000 grant from New Mexico State Forestry, through the Santa Fe-Pojoaque Soil and Water Conservation District, allowed a dramatic increase in efforts to remove invasive species over recent weeks. That brought out the chainsaws and herbicide to remove 6.5 acres of Russian olives around the preserve.
"This special cienega had these trees in this spot for 20 years, and when you go in and you take out six acres of trees, it's gonna look like you got a bad haircut. But hair does grow back," says Yvonne Hickerson, with the Institute for Applied Ecology, who is the lead for the project and wrote the grant. "The site will look raw for a while."
Treatment has to include both cutting down trees and applying herbicide to stumps. They've used Habitat, which the US Environmental Protection Agency has approved for use near water. The preserve is closed to the public until May.
Unless visitors hawkishly watched the posters displayed at the wetland this summer, or attended classes on native and non-native species removal the Botanical Gardens coordinated last year, the project is likely a surprise. Letters mailed to about 25 area homes warned that the sound of saws would be pealing from the preserve for a couple weeks.
"We anticipated there being quite a bit of resistance," she says. "To be honest, our talks were poorly attended."
The few docents who did come were supportive of the project. Mollie Parsons, education director for the Santa Fe Botanical Gardens, which manages the preserve located off I-25 near Las Golondrinas, echoed that the people who did attend sessions, which she says were advertised in newsletters and local media, were excited about the project.
"I think people understand that we live in a really delicate ecosystem and whatever we can do to protect it is really important," she says.
The intervention aims to save the cienega. Recent years have seen its moisture-loving plants, like checker mallow and milkweed, heading further downstream as the upper reaches dry out. Area monitoring wells that are part of a state hydrology study have shown the water table dropping each spring.
"When the trees leaf out, the water level drops four feet," says Scott Canning, director of horticulture for the botanical gardens. "Cienegas are one of the rarest kinds of landscapes in New Mexico, so we're doing everything we can to save it."
Those who have grown to love the trees' shade face tough news: The cover won't return. In a cienega, a spring feeds a marshy meadow of native grasses and wildflowers. Those sun-loving plants won't grow with trees overhead.
There will be impacts to bird and wildlife species that now use those trees and their fruit, Canning says, but he points to the remaining 2 acres of Russian olives on the preserve, and the areas nearby where Russian olive still thrives. The Asia native, brought in as a windbreak and ornamental addition to gardens, escaped into the wild a century ago. It has dull gray or green elongated leaves, yellow blooms in spring, and fruits from August to October that turn red as they mature. It's listed as a noxious weed in New Mexico and is among those invasive species prone to crowding out natives, like cottonwoods and willows.
Much of that dense, woody cover will ideally be kept at a distance from the cienega, Canning says. The cottonwoods can stay at the periphery of the preserve. The remaining Russian olives cluster around to shade the teaching and picnic areas, at least for now.
"Most natural cienega-type situations, you might see a few scattered cottonwoods, but wouldn't see a forest like we've seen out in the Leonora Curtin," says Bob Sivinski, a former botanist for the New Mexico Forestry Department who has advised the botanical gardens on the project. "It was such a thicket. … You couldn't even see the cienega for most of the trail because you're just walking through a tunnel of Russian olives."
He's drawn attention to the disappearances of cienegas all over the state as city and agricultural wells drain the aquifers that supply their springs.
Eventually, native shrubs like New Mexican olives and three-leaf sumacs will come back, as will wildflowers like knotty sunflower, New England aster, marsh vervain and New Mexico guara will spread. The only spot that the species of guara is found between the Sacramento Mountains in southern New Mexico and the southern Rocky Mountains near Durango is the Leonora Curtin Wetland Preserve. All of those species were at risk of dying off as the cienega dried out, he says.
"People that like the shade and like the forest are possibly going to be upset with what we did out there," he says. "What's going to benefit from this is the wetland."