We have all heard that the month of December is “the most wonderful time of the year”, according to a familiar song. December is associated with generosity, kindness and is a time to gather with family and friends to celebrate the holidays.

As we prepare for this special time of year, there is one staple that many will have in their homes: a Christmas tree. Christmas trees are an important part of the holiday season and, while artificial trees are available for purchase, close to a quarter of the Christmas trees displayed in U.S. households are real ones.

To many, Christmas trees represent love; however, what most people do not know is that to grow a Christmas tree, it takes time and it is truly a labor of love.

About Christmas Trees

Christmas trees are conifers. Conifers are trees that produce cones which contain the tree’s seeds inside (Fig. 1). Conifers usually have needle-like leaves and most of them are evergreen, which means that they keep their needles all year. Most conifers are found in the wild and, years ago, families would often get their Christmas trees from their backyard or the nearest forest. Now, conifers that will be used as Christmas trees are often grown on farms across all states, including Hawaii, according to the National Christmas Tree Association.

The two top Christmas tree producing states are Oregon and North Carolina, respectively. Oregon produces over 4.7 million trees each year, which is about 33% of all Christmas trees produced across the U.S. Meanwhile, North Carolina is not too far behind, producing close to 4 million trees annually.

While there are over 600 conifer species, the most popular one used as a Christmas tree is the Fraser Fir (Fig. 2), followed by the Douglas Fir, and the Noble Fir. The Noble Fir and Douglas Fir are Oregon’s most produced Christmas trees, while North Carolina predominantly grows Fraser Fir trees.

Unlike typical crops, where a seed is planted and a crop is harvested in just a few months, Christmas trees take years to grow. Each spring, Christmas tree farmers plant seedlings, typically planting 1 to 3 seedlings for every tree they harvested the previous autumn. However, the trees are slow growing and take 6-12 years to reach maturity, which tends to occur when they are between 6-8 feet tall. Farmers will usually harvest the trees by early to mid-November and are available for purchase by Thanksgiving.

Extreme Weather Events Impact Christmas Tree Production

Like any other crop, Christmas trees are vulnerable to extreme weather conditions. Extreme heat and prolonged periods of little to no rain (also known as drought) can cause stress to the trees, making them more prone to attract insects and diseases. It can also cause the browning and loss of needles, stunt the tree's growth, and increase the risk of the tree dying. Extreme rainfall can cause fields to flood, and this could result in the rotting of roots. Extreme cold could lead to frost damage, drying out any buds or shoots that the tree might have. While these extreme events can affect any Christmas tree, the young seedlings are usually the most vulnerable. Below are two examples of extreme weather events that impacted the Oregon and North Carolina Christmas trees industry, respectively.

Extreme heat and drought: During summer 2021, a strong and persistent high pressure system was set over the Western U.S. During mid-June to mid-July, extreme daily heat records were set across the region. This resulted in several monthly and seasonal records for the state of Oregon, including warmest July on record and warmest summer on record (Fig. 3).

The extreme heat also worsened the drought conditions in the area. By August 3, 2021, much of the West, including Oregon, was under severe to exceptional drought conditions (Fig. 4).

Agriculture was severely impacted during this time. Christmas trees were also affected; however, the degree of damage varied from location to location and by tree species, with the Fraser Firs sustaining the most damage, according to reports. The Oregon State University stated that the persistent extreme temperatures and very dry conditions were responsible for killing over 70% of the Christmas tree seedlings that were planted that year and completely drying out the needles of more mature trees. Farmers assessed the damages and tried to salvage as many trees as possible by trimming off the burned needles of the mature trees. In addition to causing financial damage to the farmers due to the loss of the seedlings, the main impact of the event that year might have affected the quality of the surviving trees and might have caused a slight increase in their prices.

Hurricane Helene: Another significant weather event that affected the Christmas tree industry, especially in North Carolina, took place in late September 2024. Hurricane Helene, in combination with a predecessor rain event, brought historic rainfall amounts that caused catastrophic flooding and deadly landslides to western North Carolina and parts of Georgia, South Carolina, and Tennessee (Fig. 5).

Most of the Christmas trees in North Carolina are planted on slopes, which protected them from the devastating floods. However, thousands of Christmas trees were lost due to landslides and other Hurricane-related events. Helene caused approximately $125 million in losses of ornamental nurseries and Christmas trees. This also includes the money and time spent growing those trees. There was also extensive damage to infrastructure and roads, limiting the access to and from the farms at the time. Christmas tree growers spent additional money to fix their infrastructure in time for the harvest season. Through their efforts and those of the North Carolina Department of Transportation, harvest season was not impacted since access to the farms was no longer an issue.

How Climate Change Impacts Christmas Trees

The Earth’s climate is warmer and, while the overall global temperature increase might seem small, this change can lead to big changes in extreme weather events, which will affect many aspects of our lives. According to the Fifth National Climate Assessment, the U.S. is already experiencing warmer temperatures and longer-lasting heat waves, and heavy precipitation, drought, flooding, wildfires, and hurricanes are occurring more frequently and/or more severely. While extreme cold events can still occur, they are becoming less frequent and intense across the nation.

A warmer climate will affect the production of Christmas trees through changes in the frequency and intensity of extreme weather events, the shifting of growing zones, and increasing the risk and prevalence of pests and disease.

Shifting growing zones: While this might not be a current concern, farmers might have to consider relocating their farms further north or higher in elevation to areas that have the ideal cool climate that is the most beneficial for the specific conifer species they want to grow as the climate changes to a warmer one.

Pests: The warmer winters and longer growing season is leading to an increase in the prevalence of pests — such as aphids, mites, and adelgids — in Christmas trees. While weather conditions can fluctuate from year to year, the United States, in general, is experiencing less extreme cold temperatures that would normally kill off most pests during winter. This allows for a larger number of pests to stay alive and continue growing in numbers. Most pests, such as aphids and mites, affect the quality of the trees by causing cosmetic damages, which can impact the number of trees that are sold. However, the Balsam Woolly Adelgid (BWA) has the ability to kill Christmas trees, in particular Fraser Firs. It has been reported that the BWA has killed about 95% of Fraser Firs found in nature across North Carolina. While the BWA has natural predators, they aren’t able to significantly control the infestation on their own. That is why Christmas tree growers have implemented integrated pest management strategies to help prevent and eliminate pests in an environmentally friendly way. This strategy uses minimal pesticides and targets the different insect lifecycles.

Disease: Phytophthora root rot (PRR) is one of the many diseases that can affect Christmas trees and it is one of the Christmas tree growers main concerns.  PRR is caused by an oomycete (also known as water mold), which is an organism that resembles a fungus. It usually occurs when the area that the tree is located is extremely wet and there isn’t proper drainage. This disease affects the roots of the trees, weakening it and eventually killing it in a short period of time. Other symptoms can include the browning and loss of its needles and wilted new growth. Additional information on other types of diseases can be found in the NC State Extension page.

The Future of Christmas Trees

The Earth’s climate is changing to a warmer one. And like most of society and the environment, Christmas trees are not adapting fast enough to these changes. While climate change is a growing concern in the production of Christmas trees, scientists at the North Carolina State University are conducting research to better understand Christmas trees' (specifically Fraser Firs) natural defense mechanisms and their ability to endure stress and become more resilient in order to survive. With this information, scientists are hoping to help the industry by producing Christmas trees that are able to acclimate and be more resilient to the threats of climate change. Think of it as a “top-notch” Christmas tree. Not only are they hoping to create the perfect Christmas trees that can withstand extreme weather events, they are also researching ways to improve the scent of the Christmas tree, and develop a tree that matures much faster (e.g. six years instead of 10) and has better needle-retention. 

Fun Facts About Christmas trees

• The 2024 White House Christmas tree was a Fraser fir harvested from western North Carolina, an area that was impacted by Hurricane Helene. 
• The 2024 Rockefeller Christmas tree (located in New York City) is 74 feet tall and it is close to 70 years old.
• Real Christmas trees are recyclable, making them a zero waste product.