Mission
Our mission is to inspire an appreciation for the beauty and value of native plants and a commitment to protect the habitats that sustain them.
Resilient Canopy Project
Mt. Cuba Center’s Resilient Canopy project aims to help adapt tree-planting strategies to meet the challenges of climate change, pests, and diseases. Trees are essential for healthy ecosystems—they produce oxygen, provide shade, and support wildlife. With this project, we analyzed which tree species native to the Eastern Temperate Forest will likely thrive in Delaware’s future climate, projected to the year 2100.
Understanding the Climate Challenge
Climate change poses a range of possible futures between one where global emissions slow down by mid-century (moderate warming), and one where they continue to rise (high warming). By 2100, Delaware could see average yearly temperature increases of 3.5°F to 9.5°F. Additionally, annual rainfall is expected to increase by about 10% (approx. 4.5”).
Our Approach
The Resilient Canopy project examined native species in the Eastern Temperate Forest region using tools like the US Forest Service’s Tree Atlas and Botanic Garden Conservation International’s Climate Assessment Tool to help predict which trees might do well in Delaware’s future climate. We also looked at how trees perform in regions that already have a climate similar to what we can expect in Delaware in the future. Although important, determining climate suitability alone is not enough to predict tree resilience. Some species already face pest and disease threats, and warming climates might allow these threats to spread, thus we also considered pest and disease risk when formulating tree recommendations.
Our Recommended Trees
We combined climate data with pest and disease risks to create six categories of tree recommendations:
Level 1. These species are likely to do well, even in a high warming scenario and do not currently have significant pest and disease concerns.
Level 2. These species are slightly less likely to thrive in a high warming scenario and do not currently have severe pest and disease concerns.
Level 3. These species will likely be stressed in a high warming scenario and/or have the potential to be afflicted by severe pest and disease concerns. We recommend that they be used cautiously.
Level 4. These species will likely be stressed in a moderate warming scenario, are likely to fail in a high warming scenario and/or have known severe pest and disease concerns. These plants should only be used sparingly and with the expectation of eventual failure.
Level 5. These species are likely to fail in a moderate warming scenario and are already generally not appropriate for our region today.
Level 6. These species may not be winter hardy today but may be suitable for future climates. They should currently be considered as experimental plantings.
You can view and download tree lists for each category here.
Conclusions
This guide provides a starting point for making native tree planting decisions in the Delaware region based on currently available data. Note that projections are estimates, and extreme weather events like heatwaves, storms, and droughts that significantly affect tree health are also expected to become more frequent in the future. Mt. Cuba has developed a monitoring system to strategically observe and measure the establishment, growth, and health of our tree canopy in order to advance our knowledge of climate resiliency and improve our decision-making and recommendations in the future. In the absence of concrete answers about what the future holds, this work is intended as a first step in making informed planting choices today in order to prepare our tree canopy to thrive in in the future.
To download the full report, click here.