There's an App for That

Scientists at UCLA and Santa Monica Mountains just added one more use of that cell phone in your pocket: battling invasive species.

By Scott Kirkwood

When John Wesley Powell made his renowned 1869 trip down the Colorado River, he described the river banks as “set with willows, boxelders, and cottonwood groves.” In fact, his exploration party often camped among willows. But 150 years later, the Colorado River corridor looks different—its banks are now dominated by an aggressive, invasive plant that is choking out the native vegetation. Tamarisk was introduced to the United States from Eurasia in the early 1800s as an ornamental plant. A water lover, the tree spreads along waterways up to 12 miles per year, and it has displaced native vegetation on an estimated 1.6 million acres of trails. Perennial pepperweed, which favors seasonal streams, is crowding out willow and sycamore, destroying shady canopy and nesting areas crucial to native birds; the plant’s deep roots are so fragile that they break off in a downpour and quickly reestablish themselves in even more spots.

After years of trying to counter these potent plants, Christy Brigham, restoration ecologist at Santa Monica Mountains, may have found a solution, thanks to computer scientists at UCLA. The school’s Center for Embedded Networked Sensing (CENS) engages citizen armies to record data on a widespread scale, sensing tremors in Mexico to predict earthquakes and tracking home-energy consumption to minimize a community’s contribution to greenhouse gases.

“CENS teams up computer scientists and electrical engineers with scientists from other disciplines and says ‘If you had really great sensors and computer technology at your fingertips, how could you do your research better?’ ” says Brigham. When the group started looking for more real-world problems to solve, someone suggested they reach out to the park for data on local invasives. Brigham not only provided them with a guide to some of the worst offenders—she urged them to focus their project on the park itself. And they listened.

Their solution was to use something that most people carry with them all the time—a cell phone. New models like Androids and iPhones are essentially small computers, able to store reference materials, communicate with global positioning satellites (GPS) and capture photos as well. A new application (or “app”) allows park visitors to view images of the most troubling species, snap photos that tag the location of the species, and send the information to park rangers so they can identify problem areas. You can visit to see the results for yourself.

The simple, elegant solution solved a laundry-list of problems. By the time an infestation can be spotted from an airplane or a satellite, the cost of removing the plants is already astronomical. Which is why the Park Service once employed two workers to spend two years hiking every trail and driving every road in the park at a cost of $200,000; days after their visits, the information was outdated, as plants spread quickly and removal projects were ongoing. Volunteers helped, too, but teaching them the difference between purple starthistle and bullthistle was time-consuming, and the park was faced with the administrative nightmare of coordinating handwritten notes, phone calls, and emails to identify locations. The new program requires little or no training, collects data in-stantly, and allows park rangers to review the information from a desktop, to confirm its accuracy. Brigham can see where data points overlap, too, rather than rely on one source alone.

The park has just begun reaching out to the general public, but the website already contains more than 1,000 data points generated by eight park employees who volunteered to carry the units around for two weeks, while going about their typical work. Compare that to 4,000 data points generated by those two industrious employees over two years.

“The amount of data we can gather is just incredible, and with all the hikers that come to our park, the potential is awesome,” says Brigham. “A lot of our local users hike the same route, or jog the same trail, or walk their dog the same five miles every day, so they’ll get clued into the invasive plants and become really powerful observers of changes in certain areas in a way that we could never accomplish with our small staff. And the educational component is great, too: People just aren’t very aware of invasive species and the damage they can do, unless they’re gardeners, and this project will really illustrate why these plants are such a problem. It also opens doors to a younger, technologically savvy audience that may not be like our typical visitor.” Indeed, only days after the new program was presented to workers on the nearby campus of software giant Google, employees rushed to the park and plotted dozens of data points on their own, something you might not expect from people who prefer the glow of a computer screen to the glow of a campfire.

Of course, identifying the plants is only one step. But Brigham hopes that once people learn more about the problem and get engaged in the solution, they may be more likely to volunteer for removal efforts. And by simply identifying the problem, the parks are gathering ammunition to request more resources.

“A lot of parks are putting in funding requests to Washington, pointing out the significant threat to our natural resources, and this information will allow them to say to the Park Service and Congress, ‘We detected 500 infestations of this heinous weed that are currently less than a hectare in size. If you give me two-hundred thousand dollars a year, I can deal with this, but if we don’t get rid of these infestations in the next five years, we’re looking at a five to twenty-million- dollar investment just to control the species, not even to eradicate it.”

Already, California state parks and other federal land agencies have expressed interest in the program, so Brigham is speaking to other land managers. CENS has created “out of the box” technology that allows any park to identify the most vicious invasives, provide reference photos, and start creating a map and web page specific to their region. What’s more, the technology can be used to identify “good” plants, too. Santa Monica Mountains is now working on a website called “What’s Blooming,” which will map the location of wildflowers in bloom so park visitors know where to head to capture photographs that are suitable for framing.

This article appears in the Winter 2010 issue.

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