Dr Andrew Hirons from Myerscough College provides an update on research supported by a research grant from Fund4Trees.
Improving urban forest establishment, resilience and performance using trait-based tree selection
By Dr Andrew Hirons
Trees greatly enrich our urban environment through their provision of a wide range of ecosystem services. However, the contribution trees make is proportional to the health of the individual tree and urban forest as a whole. Impoverished growth environments, high mortality rates and poor species diversity act to diminish the ecosystem services provided by trees and make the urban forest vulnerable to future climate scenarios.
Professionals tasked with securing the future of our urban forests will be greatly aided by robust selection guidance on tree species and cultivars. Plant traits relating to the tolerance of water deficits will be particularly valuable since water deficits frequently impose limits on tree development in urban environments and lead to early tree mortality. For example, the leaf water potential at turgor loss (ΨP0) provides a robust measure of a plant’s ability to survive low water availability since a more negative ΨP0 allows the leaf to maintain physiological function for longer in drying soils. Using a novel approach, this project aims to develop quantifiable trait-based guidance for a wide range of species that can be used by arboriculturists, urban foresters, landscape architects and tree nurseries to help establish a resilient urban forest for the future.
The Fund4Trees research grant has kindly supported this collaborative research project between Andrew Hirons (Myerscough College) and Henrik Sjöman (Swedish University of Agricultural Sciences: SLU). Please look out for the results that will be shared at future arboricultural conferences and in academic literature.
Feel free to contact Dr Andrew Hirons ahirons@myerscough.ac.uk if you would like any further information on this project. See October 2016 update below.
Dr Andrew Hirons
Myerscough College
Senior Lecturer in Arboriculture and Urban Forestry
Update (October 2016)
This year, the project has made a number of advances. During the spring and summer, we have been able to collect new data from plant material at Kew gardens and Hillier Nursery. The focus has been on species from the genus Tilia, Fraxinus, Carpinus and Ostrya but have included a range of other species particularly from Hillier. In total, there will be drought tolerance data on 46 species.
These data have contributed to the existing data-set that was collected in the previous year. I have presented some of the work at the ISA annual conference in Texas (USA). This was well received and generated a good level of interest.
During this autumn, wood density data will be collected from the species to allow co-variation in trait data to be evaluated.
The project has also been boosted by some NERC funding that will allow these data to be integrated into some species selection guidance that will be published by TDAG at the end of 2017. This will significantly increase the impact of this work and ensure it reaches professionals across the green infrastructure sector.
