Tony Kirkham, a renowned British botanist and former Head of Arboretum at Kew Gardens, dives into the pivotal role trees play amid climate change. He shares insights on how trees are adapting globally and discusses the emotional connections we have with them. The conversation highlights the importance of tree diversity in combatting pests and diseases, while emphasizing careful planting strategies to ensure their survival. Listeners can also learn about seed conservation and the personal experiences that inspire tree preservation efforts.
Climate change markedly threatens trees worldwide, with a significant portion of species facing vulnerability from pests and environmental changes.
Seed collection is vital for conserving genetic diversity, enabling the adaptability of future trees while minimizing the uprooting of existing plants.
Deep dives
The Impact of Climate Change on Trees
Climate change poses a significant threat to trees globally, with one in three species on the IUCN's threatened list. In the UK, over the last decade, planting strategies have been reevaluated to adapt to changing weather patterns. Some native species, like oaks and horse chestnuts, are particularly vulnerable to pests, diseases, and environmental pressures, leading to drastic declines. The responsibility now lies with current and future generations to preserve existing trees and plant appropriate species to ensure biodiversity.
Importance of Seed Collecting for Conservation
Collecting seeds from trees is fundamental for conservation efforts, as it helps maintain genetic diversity and supports sustainable practices. By sampling various populations, conservationists ensure the adaptability of future trees while reducing the need to uproot existing plants. Seed collection is also preferable due to the logistic advantages it offers, such as easier transport and storage compared to living specimens. The trees grown from these seeds, such as monkey puzzles from Chile, offer a glimpse of the potential diversity available to future landscapes.
Tree Planting Strategies for the Future
Future tree planting efforts should focus on species that are resilient to changing climates and environmental stressors. Strategies include ecological matching; selecting trees native to regions forecasted to have similar climates by 2050, such as red oaks from the eastern U.S. This means diversifying species beyond native options to build resilience within ecosystems, thus avoiding population homogenization. The emphasis should be on planting the right trees for specific purposes, ensuring they can provide benefits like shade and habitat for wildlife.
Observations from Global Expeditions
The speaker's extensive travels have highlighted the importance of understanding trees in their natural habitats and the potential impacts of climate change on their growth. Experiences from diverse regions, such as Chile and Taiwan, showcase how climatic shifts have allowed previously unsuitable species to thrive in the UK. Observing trees like the Douglas fir and cherry trees in Japan illustrates the beauty and fragility of these ecosystems. These firsthand experiences reinforce the need for thoughtful conservation efforts and an appreciation for the intrinsic value of trees in our lives.
Trees are ever-present in our lives and have enabled us to connect to the natural world. But should we be concerned for our trees with our changing climate and what trees can we plant in our gardens for the future?Tony Kirkham, MBE, British botanist and former Head of Arboretum, Gardens and Horticulture at the Royal Botanic Gardens, Kew, discusses how trees are adapting around the world to climate change and what we can expect to see as our future tree-lined horizon takes on a different shape.
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Alan will answer a selection in the Ask Alan podcast series from BBC Gardeners' World Magazine in February and March.