Spring buds on the sagebrush steppe are popping up weeks ahead of schedule. The same goes for the green up of aspen trees in the Tetons, both after this winter’s record-breaking warmth continued into spring.
Charlotte Cadow, a sagebrush ecologist for the Wyoming chapter of The Nature Conservancy documented sagebrush buttercups in the Nelson Knoll area of Grand Teton National Park in March, 38 days earlier than the average bloom date from the 1970s and about 21 days before 2016-2022 averages.
“It was an exciting opportunity to get out and see plants flowering in March,” Cadow said. “But also a little startling to see just how early we’re starting to see our native plant community respond.”
Her colleague, Trevor Bloom, is a PhD candidate studying this phenomenon and its ties to climate change at the University of Wyoming.
After a warm, rainy start to winter and a midseason dryspell, he saw something he didn’t expect in the backyard of his Jackson home.
“I took some samples of aspen trees that were budding on Jan. 31, in the middle of winter,” Bloom said, “which is absolutely wild.”
That same tree would reach full flower by March 22, Bloom said.
Bloom’s dissertation is in phenology, a field of study that looks at the seasonal timing of plant activity in relation to the climate. Both researchers said this year’s early bloom can be tied to the early snowmelt. The Teton region broke heat records all winter, including the warmest March days to date.
“Springtime temperatures can really prompt earlier snowmelt like we saw this year,” Cadow said. “That combination of warm temperatures, reduced snowmelt and still available moisture in the soil allows the plants to respond.”
Cadow and Bloom reference data from the Blacktail Butte area of the park that the Craighead family, well-known ecologists, collected in the 1970s.
“In general, [Frank Craighead] was seeing aspens start to bud about May 8 and leaf out near the end of May,” Bloom said. “To think that we’re seeing aspens start to leaf out on April 10 is actually pretty mind blowing.”
Bloom picked up data collection where the Craigheads left off. He said this year’s bloom has not only outpaced the benchmarks set five decades ago, but are still weeks ahead of his records from 2016 to 2022.
This year, researchers also documented sagebrush buttercup and turkey peas up to three weeks ahead of Bloom’s latest dataset.
