Hiking around the base of Blacktail Butte, Trevor Bloom reads the foliage like a book.
Where a casual hiker might see a vast sea of green peppered with yellow, pink and red flowers, Bloom spots dozens of distinct species, each in a different stage of its life cycle.
“That’s Sedum lanceolatum, common name ‘stonecrop,’” Bloom says, pointing to a glossy yellow flower. “It’s a Crassulaceaes, a C4 plant.”
As a staff phenology scientist for the Nature Conservancy’s Wyoming office, Bloom’s job is to master the identification of these plants. Once identified, he tracks their life cycle — when they first start growing, leaving, budding, flowering, bearing and dropping fruit, withering and, ultimately, dying.
On this June day, he stands on a historic bank of the Snake River, near where other wildflower-spotting scientists have trod, just a few hundred feet north of Antelope Flats Road. After identifying the stonecrop, he enters its status as blooming into his iPad.
“Every time I come out here it’s different,” Bloom says, “and I try to come out here every two to three days.”
Bloom and Corinna Riginos, another Nature Conservancy ecologist, are tackling an intensive research project that imitates and builds upon observations made by storied scientist and Moose resident Frank Craighead in the 1970s. Their trade is phenology, the study of natural phenomenon triggered by seasonal changes in the sun and temperature.
Phenological cycles around the world are out of whack from mankind’s accidental warming of the planet. Plants are emerging, developing and budding earlier as spring sets in earlier, and there’s an associated trickle-down effect on the wildlife that depends on the vegetation for sustenance and habitat.
How are plants adapting?
Bloom and Riginos are among the legions of scientists scrambling to understand how these shifting phenological cycles affect flora and fauna. In the early going of the Nature Conservancy’s examination of plant life cycles in Grand Teton National Park, Bloom says it’s too soon to say precisely how climate change is disrupting those cycles.
“It’s challenging to compare any one year to the whole set of data that [Craighead] collected,” Bloom said.
A big snow year, for example, can skew the data.
“Last year was a 600-inch year at [Teton] Village,” he said. “This year was a 500-inch year at the Village, and it’s been kind of a wet spring. I want to have a dry year in our record, to see if our extremes that we’re seeing now are more extreme.”
Preliminarily, it looks like some plants may be doing their thing ahead of schedule.
“Sagebrush, buttercup and yellowbells, I’ve seen anywhere from 10 days to three weeks earlier than anything Craighead saw,” Bloom said. “But not all of them are like that.”
The vast majority of plants that sprout in the sagebrush steppe and woodlands in and around Blacktail Butte should adapt as the climate warms. Riginos inventoried the vegetation during her initial examination, finding that 87 percent of the species’ development is tied to temperature. Serviceberry, for instance, is highly sensitive to warmth. It flowers annually once the air grows warm enough.
But phenology for the remaining 13 percent of species is strictly linked to the solar seasons — where the sun is in the sky and the length of the day.
“They’re not budging on their flowering time,” Riginos said.
Count chokecherry in that cohort of plants. Like serviceberry, it’s an important source of bear food. But one of the fruiting shrubs is more adaptable than the other.
When Craighead was observing, Bloom said, both serviceberry and chokecherry flowered and fruited at about the same time. His preliminary finding is that serviceberry now comes first, then chokecherry.
“Now serviceberry is providing berry foods for bears earlier in the summer than it was historically,” Bloom said. “How might that change bear foraging behavior? We’re not sure, but we’re interested in those sorts of nuances.”
The roots of the project
Riginos conceived of the project while on staff at Teton Science School’s now-defunct Teton Research Institute. The research limped along, using grant funding from the Meg and Bert Raynes Wildlife Fund and mostly volunteer labor from 2015 to 2017.
Riginos encountered an early hurdle when she attempted to access Frank Craighead’s raw data, logged during a five-year span in the 1970s, and again during the historically dry year of 1988.
Although Craighead popularized his phenological observations in the 1994 book, “For Everything There is a Season,” Riginos needed his original notes to develop a rigorous scientific baseline. This task alone proved an odyssey, but eventually she found them all in a box in the basement of the Craighead home, with the help of his son, Charlie. The notes weren’t always easy to decipher, due to rushed handwriting, faded text and even smoke stains from a house fire that almost claimed the observations.
“It was kind of a scientific puzzle,” Riginos said.
A Jackson native, Bloom was a natural candidate to take over the field-based portion of the study for the Nature Conservancy. His master’s thesis at Western Washington University examined how alpine plants are moving upslope due to climate change in the Rocky Mountains.
Since taking over, Bloom has developed a systematic plan and regimented routine to diligently maintain an electronic data sheet. He’s out at Blacktail Butte several times a week, literally trail running to monitoring sites selected for their varying slopes, elevation and tree cover, all the while logging “pheno-types” from 70 species of plants. The goal is to amass the detailed data for at least one more growing season, but ideally several more seasons.
Riginos hopes the findings will eventually be useful for managers. Grand Teton National Park’s efforts to restore thousands of acres of relic hayfields near Kelly and Antelope Flats could be one application, she said.
“Maybe we’re not using the species that we should prioritize planting,” Riginos said, “because they’re not so resilient and robust.”
Another management technique that the phenology data might be useful in directing is “assisted migration.” Land managers faced with a warming planet may someday elect to strategically disrupt Mother Nature, planting some species at higher elevations, or in different places, to give the plants a better chance to survive.
“Obviously, that’s a really controversial thing that I’m not advocating for,” Riginos said. “But it may come to pass that we need to do that.”
Bloom has his own hunches about how the data will someday be put to use to understand the natural interactions between Wyoming’s flora and fauna.
Perhaps mule deer whose uphill migrations are tied to the spring green-up of vegetation are following the emergence of a few plant species prime for eating. The pursuit of the most nutritious plants, sometimes called “surfing the green wave,” may be more nuanced than we know, he said.
“We’re trying to build models that could break that green wave down,” Bloom said. “They’re finding mule deer have these stopover sites. My guess is that these stopover sites correlate with specific phenology of specific species.”
Snow’s effect on flowers
An early blooming, three-petaled flower with feathery leaves catches Bloom’s eye, and he stops while headed from the valley floor to the slopes of Blacktail Butte.
“This is called prairie smoke,” he says. “Geum triflorum.”
It’s one of the first plants to emerge after spring snows burn off, he explains. That’s another variable — snowpack — the Nature Conservancy scientists are accounting for, and Bloom maintains a network of temperature sensors above and below ground at each site to gauge the annual melt. Like many phenological relationships, there’s still much to learn about the connection between prairie smoke and snow.
“I think this plant is really responsive to snowmelt timing,” Bloom says. “What I’ve found is even in the fall, when you get a thin coat of snow in September or early October, you’ll start to get these plants emerging.”
Riginos butts in.
“That’s not good for plants, coming up in the fall,” she says. “Unfortunately, we have so little historic data on things like fall phenology, because people thought things were drying out and weren’t interesting. Now we’re starting to realize what happens at the end of the season is just as important as what happens at the beginning.”