Climate change, cranberries, and their chemicals

For Lauren Erland’s cranberries, the future is now. The plants are not impressed.

Over the last two summers, Erland has been experimenting on cranberries at a Delta research farm, where the UFV berry scientist is testing how the plants will fare in a rapidly warming world.

Heating up cranberries’ environment an extra two degrees, she has stressed the plants beyond their normal limits—and they are not happy about it. The plants produced fewer berries than expected but, somewhat surprisingly, they seem to have adapted to the changes comparatively quickly. And now, with this season’s cranberries harvested, Erland and her team are set to dive inside the plant itself.

Using state-of-the-art spectrometry in UFV’s new BERRI Lab, Erland will work to find out exactly how climate change will affect the Fraser Valley’s cranberries—and the multi-million dollar industry that relies on them.

The climate change question

Two years ago, Erland posed a question: what will climate change do to her favourite berries?

Erland studies Vaccinium plants, a genus of shrubs that include cranberries, blueberries, huckleberries, lingonberries, and other related species. The fruits are important culturally, ecologically, and nutritionally to people across Canada, and especially the Fraser Valley. Pre-contact, Stó:lō people would travel to the lower Fraser Delta in fall to pick or trade for qwemchó:ls (cranberries). They also gathered blueberries and huckleberries, which were dried to last the winter, in mountainous areas around the valley.

Today, the berries are also important economically, with blueberries and cranberries making up nearly 90% of the fruit production in the Lower Mainland. BC is responsible for one-third of Canada’s cranberries: its farms produced more than 1,300 million barrels of cranberries in 2023 alone.

Climate change, Erland knew, was changing the acidic, boggy environments that cranberries thrive in. The question was by how much.

In the winter of 2022, Erland and two other researchers published a paper that used data models to predict what will happen to four berry plants in Canada: the alpine blueberry, the lingonberry, the bog cranberry, and the commercial cranberry.

The plants are well-studied on a nutritional-level—research papers laud their benefits for running, dental health, and more—but comparatively little is known about how they would adapt to ecosystem changes. Erland’s paper suggested that the ideal habitat for the plants would move north, with some current farms becoming unsuitable for cranberry production unless new varieties could be bred. It also said that the plants had the potential to be surprisingly resilient, with wild species possibly expanding their habitat as the environment warms.

It was a purely speculative study—and it couldn’t answer how climate change would affect the plants physiologically. What would happen to flowering times, growth patterns, berry yield? What changes would take place at a molecular level, and to the nutrition of the fruit itself?

Erland’s new lab has the tools to answer those questions.

Two years ago, Erland joined UFV as a Canada Research Chair to start the university’s new Berry Environmental Resilience Research and Innovation Lab—BERRI Lab for short. (Erland applied for the position because she envisioned the pun and felt it was a sign.)

She began overseeing the construction of a multi-million dollar Chilliwack laboratory that would give her and her students the equipment they needed to see the molecular changes happening to the plants.

“What we’re doing in the lab is all of the decades—hopefully—of follow-up work to understand, if we think this is what will change the environment, what will actually happen to the berries,” Erland said.

It is a big goal, and one that will involve detailed experiments and precision testing over many years. Now, after roughly two years of construction, Erland has a fully equipped lab to do it in.

But before she could go inside the cranberry, she needed some unhappy plants. She had to get onto a cranberry field.

In the field

There are two ways a scientist like Erland can learn how climate change will affect a plant. The first is in the lab by creating perfectly controlled climatic conditions that can isolate one specific element, like heat or precipitation. The second, more chaotic option, is on a farm.

That is what Erland chose, so she could use enclosures to raise the temperature of the environment around her test plants while still getting the variability of a natural field ecosystem.

“It’s really good because we get all of the other conditions that you see in the field,” Erland said about the field studies. “So when it’s hot, it’s two degrees hotter. When it’s cool, it reflects the true environmental changes we’re seeing.”

In 2023, Erland established a three-year partnership with the BC Cranberry Marketing Commission that gave her access to the organization’s well-established research farm in Delta. The research farm, which is managed by cranberry growers, is home to a variety of experiments, including herbicide control studies, new variety trials, and pesticide product screening.

In the spring of 2023, Erland began her in-field trials to study how different varieties of cranberries respond to warmer conditions. To do so, Erland and her team built little plexiglass cases for the cranberries (with sensors inside and out to document exactly what was happening in the environment), covered the shrubs with each container, and increased the temperature by two degrees.

In the first season of the experiment, Erland and her team saw some results they expected; flower development is temperature-dependent, and the heated cranberries bloomed earlier than normal. But other phenomena were a surprise.

“We’re actually seeing—I’ll be honest—much bigger changes than I ever expected to see,” Erland said.

Erland found that the cranberry bushes produced a lot of runners—horizontal stems up to six feet long that take root into the ground and form a dense mat of plant material. Some runners are fine, Erland explained. A lot means that the plant is spending more energy expanding rather than producing buds. And without buds, there are no cranberries the following year.

Cranberries typically have a two-year cycle: buds that are produced one year bloom into berries the next.

“You’d expect to see a delayed response,” Erland said. “If you apply fertilizer to cranberries, it takes you two years to see your full results.” But the berry production in 2023 took a hit even with the plants having buds from a pre-experimental season. And this year, instead of another decline, berry production was back up.

“Just from the amount of cranberries that we saw in our bins as we were harvesting this year, it looks like some of the varieties—with a year to adapt to the conditions—do seem like they may be bouncing back already,” she said.

She cautioned that the results could be just the natural “wobble” of the cranberries’ cycle, which is why her study will last at least three years in order to establish a better baseline for what the cranberries do in the field.

The better yield could also be because 2024 was just an easier summer on plants in general.

In 2023, the BC berry industry had a hard year, with a cool spring and then unseasonably high temperatures during the bloom period. BC blueberry producers had their smallest crop in over a decade. High summer temperatures also put stress on the berries, resulting in abnormally small blueberries across the board. (Cranberries, paradoxically, did better last year than they had for almost a decade—although that was likely because farmers are exchanging old crops for new, higher-yielding varieties.)

This year, Erland said, “it seemed like a way less stressful summer to be a plant.”

With her cranberries harvested—and many of the neighbouring plants on their way to be turned into craisins or juice—Erland is now ready to take them into the lab for some state-of-the-art spectrometry.

In the lab

Plants are full of chemicals—though not in a conspiracy-theory way.

Unlike people, plants can’t get up and walk away when their environment becomes bad, so they use highly sophisticated chemical-sensing and -response systems to manage instead. Plants use neurotransmitters like melatonin (the sleep hormone) and serotonin (the happy hormone) to understand and respond to their environment.

To find out what is going on inside her stressed cranberries and look at the chemicals accumulating inside their cells, Erland will use a process called liquid chromatography mass spectrometry. (It’s like bloodwork, but for plants.) After grinding up pieces of the leaf or berry and soaking it in solvents, Erland will put the sample into the million-dollar machine and separate out the 70,000 different molecules contained inside. She will look at how molecular proportions are changing due to climate change, or how increasing temperatures are impacting one particular element—say the pigments that make cranberries red and give them their antioxidants.

“It really helps us get to this next level of understanding of what’s going on,” Erland said.

“We can integrate things from standing in the field with a grower who has seen changes and … we can take that into the lab. We can understand, hypothetically, on a biochemical level how all of that is changing. And then, from that [we can] go back to the grower and say ‘We know these are the systems that are changing in the plant. If we can come up with a management practice or management strategy that targets that system, maybe we can make it more resilient.’”

Over the winter, Erland will be looking at the differences between varieties to see which ones have responded better, or worse, to the artificial climate change. From there, she’ll be able to start giving advice to growers looking to prepare for a hotter, harsher future.

“A cranberry field can be productive for 50 years, it’s a very long-lived crop,” Erland said. “Growers know that, that’s why they’re asking for this. So on a very high level, we’ll give recommendations for replanting, suggestions for what they might expect to see in terms of differences in management.”

“And then of course, I’m a scientist at my heart,” she continued. “So being able to understand what’s actually happening in those plants—we can generate that fundamental knowledge to ask the questions that we don’t even know we need to ask.”

What’s next for cranberries

There is still at least one more year left for Erland to see how cranberries at the Delta research farm respond to climate change—but the end of the field study won’t be the end of Erland’s research into Vaccinium and their future.

Her team—which includes postdoctoral fellow Sarah Lane, PhD student Dan Gaudet, and several undergrads—has already begun studies to examine the impacts of wildfire smoke on seeds, and has plans for joint research on leafhoppers with the University of Laval.

Erland also hopes to launch more collaborations between First Nations, growers, and governments to make sure cranberries, blueberries, and other fruits can continue their important role in the Fraser Valley—both culturally and economically.

“It’s big business here,” Erland said. “The whole reason they created my position at UFV was because … the grower community said, ‘We need this kind of information.’ This whole program really is the university’s response to the community identifying a gap in knowledge.”

“I am just at the beginning of my career, and I don’t plan on retiring anytime soon,” she continued. “I would love if people would put me out of business and we could rein [in] climate change and it wasn’t going to be a problem—but I don’t think that’s happening anytime soon.”