Expert explains effects of catastrophic weather events on forests and tree species

This year has seen its share of severe weather—but how do these powerful storms impact forests over the long term? A Virginia Tech forest health expert breaks down the long-term effects catastrophic weather events can have and how to revive hard-hit forests. 

Forest recovery

Forests can recover from large-scale disasters through natural succession, though it may take years to resemble their original state, depending on the damage. “Disruptive weather events can set back, accelerate, or completely change the course of succession and the resulting mature forest that was once present,” Carrie Fearer, an assistant professor in the College of Natural Resources and Environment shared. “However, appropriate human intervention can speed up restoration to help the forest look more like its original form.”

Certain forests or tree species tend to be more vulnerable to extreme weather. “Forests that are most vulnerable are those that are either very young or very old because they do not have the structural integrity to withstand weather events,” Fearer said. “Trees with a deep, expansive root system are typically able to withstand more extreme weather events because of the protected structural support that roots provide.” 

Species and extinction events

”Since invasive species can colonize degraded sites much faster than our native species, there is the risk that native plants could be outcompeted by nonnative, invasive plants in these affected areas,” Fearer explained. “This is especially true for threatened or endangered native species that only exist in certain environments, so extreme weather events could increase the risk of extinction or at least extirpation from that area.”

Climate change

There is considerable debate about the impact of climate change on catastrophic weather events. Fearer shared that climate change will only continue accelerating the frequency and intensity of such occurrences. “It will increase the likelihood of catastrophic weather events occurring in areas that they did not use to occur, leaving vulnerable species exposed to weather events that they cannot recover from,” she said.

Strategies to adapt to the impacts of extreme weather events

Forests are responsible for many important ecosystem processes, including erosion protection, nutrient cycling, photosynthesis, and water and air purification. Long-term effects on forests may lead to more nutrient runoff from agriculture and other systems that could impact local communities. 

“Maintaining healthy forest conditions, including reducing soil erosion, planting native species, removing invasive species, and encouraging a healthy forest understory, can all help reduce the impacts of extreme weather events,” Fearer said. “In addition, prescribed fire conducted by trained professionals can be a successful management strategy to encourage species regeneration and healthy ecosystem conditions in fire-tolerant ecosystems, like forests within the southeast.”

Best species of trees to replant with 

Planting native trees that are appropriate for the site and climate conditions will be the first step in helping to restore ecosystems. “Researching the native species and promoting practices that encourage healthy growth in trees, such as planting at appropriate depths, appropriate watering and fertilizing, and preventing pest/pathogen damage, can help restore ecosystems by limiting the stress placed on the trees, making them less vulnerable to weather events,” Fearer said. These strategies will help speed up succession to achieve a sustainable climax forest that can withstand weather-related events.

– Written by Meredith Murphy

About Fearer

Carrie Fearer is an assistant professor of forest health in the Department of Forest Resources and Environmental Conservation at Virginia Tech’s College of Natural Resources and Environment. Her research focuses on forest pathology, early disease detection, and microbes in tree health. Fearer gained international recognition for identifying the cause agent of beech leaf disease, a new threat to the global nursery trade and native beech species across North America, Europe, and Asia.

Interview

To schedule an interview with Fearer, contact Margaret Ashburn in the media relations office at [email protected] or 540-529-0814.