In the spring of 2018, University of New Brunswick forestry professor Anthony Taylor embarked on a research journey prompted by a seemingly innocuous observation: swathes of red-tinged trees along a highway. These trees, identified as dead balsam firs, sparked a multi-year investigation culminating in a recently published study in the journal “Frontiers in Forests and Global Change.” The study pinpoints the cause of the widespread balsam fir mortality in western New Brunswick and eastern Maine as a lethal combination of drought and high temperatures, both consequences of the changing climate. This die-off, alarming in its scale, underscores the vulnerability of this iconic Canadian tree to the escalating effects of global warming.
The balsam fir, comprising approximately 20% of New Brunswick’s tree population, holds a special place in Canadian culture, particularly during the Christmas season. Its fragrant needles and classic triangular shape make it a popular choice for Christmas trees, with the province exporting around 200,000 annually, primarily to the United States. The significant die-off observed in 2018, therefore, posed not only an ecological concern but also a potential economic threat to the Christmas tree industry. Taylor and his co-authors, James Broom and Loïc D’Orangeville, meticulously analyzed various potential causes, ranging from pest infestations to climate data. Their findings unequivocally pointed to the 2017 drought, marked by a warm, dry summer and a scorching fall, as the primary culprit.
The research team discovered that balsam firs are particularly susceptible to drought stress exacerbated by high temperatures. The 2017 weather conditions severely stressed the trees, leading to their demise the following year. Further investigation into historical data revealed a similar pattern in 1986, where balsam fir mortality was linked to a comparable drought and heatwave the preceding year. This historical precedent strengthened the study’s conclusion, solidifying the role of climate as the driving force behind the observed die-off. The findings raise serious concerns about the future of balsam fir populations, especially given the predicted trajectory of climate change.
Experts in the Christmas tree industry corroborate the study’s findings, acknowledging the impact of climate change on balsam fir and other tree species. Fred Somerville, president of the Canadian Christmas Trees Association, highlighted the balsam fir’s preference for cold winters and damp summers, conditions increasingly disrupted by the unpredictable weather patterns associated with climate change. While excessive heat poses a threat, the more immediate concern is the lack of sufficient rainfall. Young trees and saplings are particularly vulnerable to drought, while older trees exhibit stunted growth and a less vibrant green hue, diminishing their appeal as Christmas trees. Matt Wright, a Christmas tree farmer in Nova Scotia, echoes these concerns, noting the broader impact of climate change on conifers, including balsam fir. He observes that heat stress affects the trees’ root systems, making them more susceptible to emerging pests.
The changing climate has also altered the population dynamics of certain insects, particularly those that overwinter in the soil. Milder winters and the absence of deep frost disrupt the natural regulation of these pests, enabling them to emerge earlier and in greater numbers. This, coupled with the weakened state of the trees due to drought and heat stress, creates a perfect storm for pest infestations. Taylor emphasizes the synergistic effect of climate change and pest vulnerability, noting that weakened trees are less able to defend against pests and diseases. He advocates for further research to fully understand the interplay between climate change, pests, and the future of Christmas trees.
Addressing the challenges posed by climate change requires a multi-pronged approach. Taylor suggests planting diverse tree species to enhance forest resilience and implementing robust weather monitoring systems to track changing patterns. He underscores the urgency of action, citing the record-breaking warmth of recent years and the prediction that 2024 will be even hotter. While the 2018 balsam fir die-off was an anomaly, such events are likely to become more frequent with a warming climate. The long-term survival of the beloved balsam fir, an integral part of Canadian tradition and industry, hinges on mitigating the effects of climate change. Without intervention, the iconic Christmas tree could become a rarity in the coming decades, leaving a void in both the landscape and the holiday season.
