A surreal illustration of a Fremont cottonwood tree, representing adaptation to climate change.

Climate Change and Trees: Can Phenotypic Plasticity Save Our Forests?

Samir D’Costa in Climate & Environment August 2025 • 4 min read.

"New research reveals how a tree's ability to adapt its behavior could be key to surviving a rapidly changing climate."

The relentless march of climate change is reshaping our world, and few ecosystems are feeling the pressure more acutely than our forests. As temperatures rise and environmental conditions become increasingly unpredictable, the ability of plant species to adapt and survive is being pushed to its limits. While some species might migrate or face decline, others possess a remarkable tool for survival: phenotypic plasticity.

Phenotypic plasticity refers to the capacity of an organism to alter its physical and behavioral traits in response to changes in the environment. Think of it as a plant's ability to 'learn' and adjust to new conditions. This adaptation might involve changes in the timing of key life events, such as when trees produce leaves or set buds, allowing them to better align with the altered seasons.

Recent research published in Global Change Biology sheds light on the crucial role of phenotypic plasticity in the survival of Fremont cottonwood trees (Populus fremontii). This study, led by Hillary F. Cooper and colleagues, investigates how genetic and environmental factors influence the phenology (the timing of biological events) of these trees, revealing valuable insights into the adaptive potential of forests in the face of climate change.

How Does a Tree Change Its Stripes? Understanding Phenotypic Plasticity in Fremont Cottonwoods

A surreal illustration of a Fremont cottonwood tree, representing adaptation to climate change.

The researchers focused on two key phenological traits in Fremont cottonwoods: bud set (when trees form buds in the fall to prepare for winter) and bud flush (when buds open and leaves emerge in the spring). By studying trees from 16 different populations across Arizona, planted in three common gardens with varying climates, the team teased apart the genetic and environmental influences on these traits.

The study revealed significant genetic, environmental, and interaction effects on both bud set and bud flush. This means that both a tree's genes and its environment play a crucial role in determining its phenology. However, the degree of plasticity varied depending on the origin of the trees.

Genetic Variation (G): Differences in genes influence phenology.
Environmental Influence (E): Climate and location matter.
Gene-Environment Interaction (GxE): Genes and environment combine to affect bud development.

Trees from hotter, drier climates displayed greater plasticity, exhibiting more flexibility in their bud set and bud flush timing. In contrast, trees from colder, frost-prone regions showed less plasticity. This suggests that the ability to adapt phenology is itself an adaptation shaped by the climate a tree experiences.

Adapting to Change: What Does This Mean for Our Forests?

The findings of this study highlight the importance of understanding phenotypic plasticity in the context of climate change. As temperatures continue to rise and environmental conditions become more erratic, the ability of trees to adapt their phenology will be crucial for their survival. While this research focuses on Fremont cottonwoods, the implications extend to forests worldwide.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1111/gcb.14494, Alternate LINK

Title: Genotypic Variation In Phenological Plasticity: Reciprocal Common Gardens Reveal Adaptive Responses To Warmer Springs But Not To Fall Frost

Subject: General Environmental Science

Journal: Global Change Biology

Publisher: Wiley

Authors: Hillary F. Cooper, Kevin C. Grady, Jacob A. Cowan, Rebecca J. Best, Gerard J. Allan, Thomas G. Whitham

Published: 2018-11-14

Everything You Need To Know

What is phenotypic plasticity and why is it important for trees facing climate change?

Phenotypic plasticity is the capability of a tree to alter its physical and behavioral traits in response to changes in its environment. It allows trees to 'learn' and adjust to new conditions, such as changes in the timing of key life events like leaf production or bud setting, which is crucial for survival as temperatures rise and environmental conditions become more unpredictable due to climate change. Understanding and leveraging phenotypic plasticity could be a key strategy in helping forests adapt to the challenges posed by a rapidly changing climate.

How do genetic variation and environmental factors influence the timing of biological events (phenology) in Fremont cottonwood trees?

Research on Fremont cottonwood trees demonstrates that both genetic variation and environmental factors significantly impact phenology, specifically bud set and bud flush. Genetic differences (G) influence the phenology of trees, while the climate and location (E) also play a crucial role. The interaction between genes and the environment (GxE) further affects bud development. Trees from hotter, drier climates exhibit greater plasticity, showing more flexibility in bud set and bud flush timing, whereas trees from colder regions display less plasticity, indicating that the ability to adapt phenology is shaped by the climate a tree experiences.

What did the study in Global Change Biology reveal about phenotypic plasticity in Fremont cottonwood trees, and who conducted it?

The study published in Global Change Biology, led by Hillary F. Cooper and colleagues, revealed the critical role of phenotypic plasticity in the survival of Fremont cottonwood trees. The research investigated how genetic and environmental factors influence the phenology, specifically bud set and bud flush, of these trees. The findings showed that trees from different populations exhibited varying degrees of plasticity depending on their origin, with trees from hotter, drier climates displaying greater adaptability. This highlights the importance of understanding phenotypic plasticity for forest survival amid climate change.

What are 'bud set' and 'bud flush' in the context of Fremont cottonwood trees, and why are they important for understanding adaptation to climate change?

Bud set refers to when trees form buds in the fall to prepare for winter, while bud flush is when buds open and leaves emerge in the spring. These two phenological traits are crucial for understanding how Fremont cottonwood trees adapt to climate change because their timing directly affects the tree's ability to survive and thrive in changing environmental conditions. Studying bud set and bud flush helps researchers determine the extent to which trees can adjust their life cycles in response to rising temperatures and altered seasons. Further research into the genetic and environmental factors influencing these traits can help inform conservation strategies.

If Fremont Cottonwood trees from hotter climates have greater plasticity, can we relocate trees from warmer climates to help trees adapt to climate change?

While it's true that Fremont cottonwood trees from hotter climates have demonstrated greater phenotypic plasticity in bud set and bud flush, directly relocating trees from warmer climates to colder ones as a climate adaptation strategy is complex and fraught with potential risks. Such an approach would need to carefully consider gene-environment interactions (GxE), as trees from warmer climates might not be fully adapted to the day length, soil composition, or other biotic stressors present in the new environment. Furthermore, introducing new populations could disrupt local ecosystems, outcompete native species, or introduce diseases. More research is needed to understand the long-term consequences of such interventions and to identify the most effective and sustainable ways to support forest adaptation.