Hillside with spring flowers, new study field site

Early season at a new field site

The five-week start to our summer field season in Colorado’s Elk Mountains did not go as planned. Field science is the art of intense planning followed by straying. Field time leads to new insights that inform the research, while other times straying from the plan is due to mistakes or chance events. Both are a huge part of scientific discovery.

As a plant-focused scientist within a mountain watershed study, our aim for these five weeks was to select and establish study plots for an early snowmelt experiment. Last summer, I had picked out four study sites across an elevation gradient. The sites range from montane hillslopes with sagebrush (Artemisia tridentata) to subalpine ones covered by high elevation specialist species, such as a rose-family plant called creeping sibbaldia (Sibbaldia procumbens).

In a year’s time, we will be melting snow earlier in half these study plots with the other half as controls. Snowmelt provides water resources needed for mountain plants to grow. We expect that drought-adapted species like sage will grow earlier to benefit from the water, risking frost damage to young leaves. We expect the high elevation specialists to be more conservative, risking insufficient water to ensure leaves don’t grow before temperatures remain above freezing. Either way, the timing of growth by mountain plants could alter how much water makes it to the river and influence one of the most critical resources provided by mountain systems.

Our first mishap of the field season was due to snow. Early in the season, snow blocked the dirt road through a forested stretch, where there wasn’t as much sun coming through. Chelsea, my field assistant, and I were willing to try once to get through but got stuck. The truck behind us towed us out, figuring it would have been them in the snow if it hadn’t been us. Our plan shifted to hike up the road to our study site. It wasn’t a long hike, about a mile, and for the return trip we chose a cattle path on a moraine-formed hillslope. Hiking provided a view of the backside of the hillslope that I’d missed in my reconnaissance the previous year. The snow that blocked our way on the road guided us to a more accessible and comparable hillslope to the other study sites, improving our study design.

Vole-chewed cables: not what you want to find in the field!

Vole-chewed cables: not what you want to find in the field!

Our second mishap is better told after the third one, which was a critter-caused conundrum. The voles that thrive on the mountain hillslopes we study had pawed through the equivalent of dense vole-sized barbed wire screen. It was the Achilles heel in the expensive and time-intensive system of steel casings that I’d set up to prevent critter damage to the 64 soil temperature and moisture sensors I’d set up the previous summer in a long-term climate warming experiment. In less than a week, the voles had chewed through 14 of our 64 sensor cables, leading to lost data.

We jumped to action to minimize further damage, then began the slow process of field soldering wires on some of the hottest, driest days of summer. Temperatures in Phoenix, Arizona were nearing 120 °F (49 °C). Our hillslope air temperatures were in the 90’s °F (30’s °C). I’m not ready to find out what a warmer world will be like.

We had lost data and, compounding our frustration, the computer batteries kept failing. Nothing was going as planned. Chelsea went to get a new battery and I took 10 minutes to walk around the experimental site in the heat of mid-afternoon under a cloudless sky. If the voles hadn’t come to feast on the cables, we wouldn’t have had wires to repair and I wouldn’t have been there.

What I saw wasn’t anything exceptional, but may be an observation critical to our project. Past studies have shown that many of the mountain plant species build different leaves when drought stressed – leaves that lose less water. But in doing so, they reduce how much sugar they can make through photosynthesis for the growing season. They can’t hit ‘undo’. They can only redo by losing the drought leaves and producing new ones, which is costly.

Folded lupine leaves in the field

Folded lupine leaves

What I hadn’t realized was that many other plant species were folding their leaves to save water. Also, a folded leaf, especially if the leaf is white and fuzzy underneath, reflects more of the sun’s energy, reducing overheating on cloudless afternoons.

A folded leaf can unfold if and when rain events occur. Folding allows greater flexibility within a growing season should rain come and may be a critical adaptation for plants to succeed when snow melts early. Quantifying the timing and duration of leaf folding and its consequences on water retention and loss will now be integral to our study.

Field science is unscripted. Many things don’t work and sometimes you have to complete a lot more work to fix what didn’t work. But, it also can be the added time invested on a field day that was not planned that leads to new insights. Let’s get back to the second mishap that led to an important insight for me as a faculty mentor.

How can you tell if someone will be a good field scientist? You can tell by watching their reaction when your keys descend down into the depths of an outhouse. When this happened during the second week of our field season, Chelsea’s reactions were to laugh, be patient, and then hold the flashlight during the retrieval. It’s the accidents of field work that test us and determine whether we can learn from what doesn’t go well.

Soon after the second mishap, Chelsea was in town (Crested Butte, CO) and was asked by a local if she was a scientist. She wasn’t sure how to answer. She’d only just earned her B.S. in Biology. She has toughed it out through a rough start to our field season, laughing and learning from the mishaps. ‘Yes’, I said, ‘You are definitely a scientist’.