Once winter nights dip below freezing and the days warm up above freezing sap begins to flow in sugar maples marking the start of the syrup season. U.S. maple syrup production is a global industry, which has been increasing by nearly 10 percent per year over the past decade according to the USDA’s National Agricultural Statistics Service 2017. With climate change, daily temperatures are on the rise, which affects sap flow and sugar content. By 2100, the maple syrup season in eastern North America may be one month earlier than it was during 1950 and 2017, according to a study published in Forest Ecology and Management.
The study examined six sugar maple stands from Virginia to Québec, Canada, over a six-year period. The sugar maple stands are located in: Divide Ridge in southwest Virginia; Southernmost Maple in central Virginia; Indiana Dunes National Lakeshore in Indiana; Harvard Forest in Massachusetts; Dartmouth Organic Farm in Hanover, New Hampshire; and Chicoutimi in Québec, Canada.
Maple syrup production is impacted by two climate sensitive factors: sugar content, which is determined by the previous year’s carbohydrate stores and sap flow, which depends on the freeze/thaw cycle. As a sugar maple tree thaws, the frozen sap begins to move through the tree.
The research team sought to test how monthly and season-long average temperatures during the tapping season, and temperature and precipitation from the preceding year, affect sap flow.
Each day of the tapping season (from January to May) across the study regions, researchers obtained sap samples from 15 to 25 mature sugar maple trees. They measured the volume and weight of the sap and conducted an analysis of the sap’s sugar content. Daily temperature readings were also taken. With this data, the team could then look at the annual variability of the sap flow, to see how the data varied from tree to tree and from year to year.
Based on historical climate data, the researchers examined how past changes in minimum and maximum temperatures affected sap flow at each of the sites. They created a model that predicted the timing for optimal sap flow based on historical temperature data pertaining to the freeze-thaw days, actual sap collection from their fieldwork, and monthly climate. To calculate projections on how climate change will affect maple syrup production, the team used climate models based on the RCP 8.5 carbon emissions scenario, which follows current emissions trends.
The study found that most sap collection seasons were 45 days or fewer and that the middle of the sugar maple tapping season tended to fall in March or later for three-quarters of the sites.
According to modeling projections, by the end of the century, the team found that tapping season is projected to be, on average, one month earlier. In addition, it is likely that by 2100, Virginia and Indiana will barely be able to produce any sap while production in Québec will be considerably enhanced. Of the states in the study, New Hampshire and Vermont (not one of the sample sites but for which climate data was analyzed) are likely to be the least affected but will still experience decreases in syrup production. By the end of the century, most of the areas containing sugar maples in the U.S. are projected to see decreases in maple syrup production while areas in northern Ontario and Québec may see moderate to large increases in production. In addition, the concentration of sap sugar is likely to become lower and more variable (28-36% lower across the modeled sites).
“As the climate gets warmer, the sugar maple tapping season will shrink and will get closer to a December date. Maple syrup producers may want to consider adapting their technologies and collection logistics in advance, so that they are prepared for how climate change is going to affect production,” said co-author David Lutz, a research assistant professor of environmental studies at Dartmouth.
In the U.S. alone, maple syrup production was valued at $141 million in 2017 according to the U.S. Department of Agriculture. As for world share, the Federation of Québec Maple Syrup Producers reported in 2017 that Canada is home to 80 percent of world maple syrup production of which 72 percent is produced in Québec, and 20 percent is produced in the U.S.
The researchers call for additional studies on climate change and maple syrup production, which can help maple syrup producers, forest managers and policymakers prepare for changes that are already impacting a multimillion-dollar industry.
The oft-memed slogan “save the bees” has been all the buzz for several years now, but who is actually making an effort to save one of the planet’s most important insects?
Penn State’s prominence in the world of agriculture is well-known. The farms around University Park draw crowds for multiple farms shows each year, while the university’s agricultural and forestry programs rank within the top 10 worldwide. Gameday tailgates and Creamery ice cream pasteurized at our convenience are sure signs of Penn State’s agricultural prowess in the everyday lives of students.
What would happen, though, if the agricultural world and therefore the entire planet lost one of its most import resources due to declining populations?
ENT 222: Honey Bees & Humans, a course focused on the life and prominence of the Western Honey Bee, addresses the possible solutions to this problem. This popular gen ed explains not only why humanity should make an effort to save these crucial members of Earth’s ecosystems, but also how to go about it.
ENT 222 students observe the insect world in the Arboretum and take frequent field trips to the apiaries (where the bees are kept, off Orchard Road) on the Blue Bus. Through these experiences, they become their own researchers, formulating their own questions on what would happen if a single major entity in the circle of life were to go extinct.
The idea for the class originated when Dr. Harland Patch, assistant research professor, and his wife Dr. Christina Grozinger, distinguished professor of entomology and director at the Center for Pollination Research, decided to share their love of bees with fellow Penn State alum Maryann Frazier. Frazier, a 1980 graduate who majored in bee husbandry and later earned her Master’s of Agriculture in 1983, knows how to raise honeybees. Bringing a practical side to the couple’s already in-depth bee research, she allowed Patch and Grozinger to take their lab-based insight into the field.
The first half of Grozinger and Patch’s class covers the physiology of the honey bee. Understanding bees and their entomology are critical in understanding why pesticides kill them and therefore harm agricultural production. Patch Challenges his students with questions such as: How do we use pesticides in a way that doesn’t harm species?
The second half of the course dives into how humans have relied on honey since the beginning of time, utilizing bees’ work to bolster their micro-nutrition.
“People all over the world have thought of bees as being associated with the good life,” said Patch. “Israel is known as the land of milk and honey.”
Students also learn how evolution has influenced agriculture over time, as well as the effect of cultural influences like the success of large pesticide companies.
The triad also asks students to channel their majors. They know not everyone will be as originally enthralled in entomology as they are, but everyone brings something to the table. Bee politics, as explained by Patch, confirms that the solution is in thinking that anyone can help solve the problem, not just scientists.
“A business person, whatever you do in life, anyone can be conscious and find solutions, because they’re collective solutions,” Patch said. “We ask students to channel their majors. For example, econ majors can observe the tomato plants of the Arboretum, then write about how bumblebees contribute to the pollination of tomato plants, how tomatoes can be used for a lot of things, and how important this is for the economy.”
Though the class addresses an alarming concept, his students’ progress helps him to remain hopeful about the world’s bee crisis.
“This takes us to why we teach the class. My optimism is in what Penn State students do. The hope is that they will raise awareness to how people make decisions in the world,” he said. “I’m optimistic in that the students will do something when they’re my age, or they’ll be aware of it.”
Through the lenses of his glasses Patch’s eyes widen as he discusses his favorite topic over his desk. A giant honey bee poster hangs in his office.
“They look for a story here. The purpose is to slow down, try not to multi-task, and try to observe the world for yourself; the natural world, unmediated, and come out with your own experience of the thousands of questions nature has to offer,” he said.
“The question of honeybees and their challenges is what we do — if we just think these thoughts and do nothing, nothing happens in the world.”
There’s a reason the waiting list for this gen ed seems to always overflow: Students want to solve real-world problems in a way that expands their mindset outside the classroom. Plus, there’s nothing like a tailgate-saving cause.
“If we didn’t have bees, we wouldn’t have tomatoes,” Patch said. “And hot dogs would be a lot less fun.”