I had a moment of panic last week. It was the crocuses that did me in, if you can believe it! Well, the crocuses and climate change. I’m a scientist, and an experiment was on the line.
This year will mark four years of spring phenology monitoring in Bole Woods. Phenology is the study of the timing of natural events, and we’ve been monitoring the timing of the spring greening of Holden’s forests. This sort of monitoring helps us understand how species may (or may not) be able to track the changing climate, and anticipate potential changes in our natural world.
Next week, we start our thrice-weekly hikes out into Bole Woods where six dedicated volunteers will dutifully photograph the exact same canopy trees and scour the forest floor looking for signs of emergence of some of our most stunning forest wildflowers: trillium, trout lily, squirrel corn, and Dutchman’s britches.
We want to know – when will our canopy trees put on leaves this year, rendering the forest floor deeply shaded? And when will those stunning wildflowers emerge and flower? Is the timing of these things dependent on the weather? Will shifts in the timing of these events render the wildflowers with more or less time in the sun, before the canopy leaves shade them?
But, to answer these questions accurately, we’ve got to get out there to start observing well before they do anything. Last year, our spring wildflowers popped about two weeks earlier than usual (starting around the March 24th), thanks to a very mild winter. But, this winter (through February, at least) was much colder and snowier than last year. I was feeling satisfied that we had time to get out there and start monitoring. And then… March. There was a day last week that pushed 60°F! It was sunny, too. The daffodils in my yard must have grown three inches last week and those crocuses are about to pop. The neighbor’s crocuses are in full bloom!
We desperately need baseline data in Bole Woods… an observation or two in which the canopy is still fully open and no spring ephemerals have started nosing up out of the ground. And so, I texted my lead technician, Emma Dawson-Glass, and asked if she’d be willing to hike out there and check. The weather was spectacular and she was happy for the hike. Good news… everything was still tucked into the soil, save for a precocious (and beautiful) spring beauty just poking its head up.
And so next week we’re all in, with boots on the ground in Bole Woods. Our tenacious volunteers will be checking at regular intervals so that we can accurately report the first date of the spring ephemerals popping up out of the ground and the first leaves on our forest canopy trees. Will this year be early, like last, thanks to the warm March days we’ve had, or will the colder January and February prevail and drive a more typical timing of spring events in our forest? We’ll know in the next few weeks!
Katie Stuble is a scientist at Holden Forests & Gardens. She and her lab conduct research into the ways in which species interact with one another, how this shapes our natural world, and how this information can inform restoration. Katie has a PhD in Ecology and Evolutionary Biology from the University of Tennessee, an MS in Ecology from the University of Georgia, and a BA in Biology from St. Mary’s College of Maryland.