Adaptation of Ash (Fraxinus excelsior) to Climate Change

Carried out by: Jo Clark, Bangor University

Summary Description:

The aim of this part-time PhD is to test the adaptability of native ash from a range of UK locations to the predicted climate in 2080.
The specific objectives are to:

  • identify provenances of ash that may be closely matched to the future climate and to test them in the current climate through a series of reciprocal transplant experiments
  • determine the phenology of ash provenances in relation to their suitability for growing in the predicted climate of 2080
  • determine the stratification (cold pretreatment) requirements of the seed of ash provenances
  • determine levels and effects of outbreeding depression

Timescale: 2006-2013

SFT Funds Awarded: £10,000

Project Outcomes:

Climate-matching data were used to identify ten provenances and five sites for a series of reciprocal transplant experiments along a latitudinal gradient from northern Scotland to the Pyrenees.  Survival and growth have been measured over three years (2009-2011).  So far there is very little indication that local provenances grow better than non-local ones, but monitoring of the experiments will continue.

It has been shown that provenances have different chilling requirements for both bud burst and seed germination, with northerly provenances requiring a longer period of chilling than southerly ones.  If winters in the UK become warmer, as predicted by climate change models, bud burst of trees in native populations of ash may be delayed and natural regeneration may be less successful

Jo completed her PhD and passed her viva in July 2013 and her completed thesis is available to download and read here.  She is now the Forestry Research Manager for the Earth Trust based in Oxfordshire. Jo was also awarded The Scottish Woodlands Student Excellence Award in recognition of her considerable efforts to complete an excellent project.

Further Information

Is there adaptive potential in ash to cope with climate change?
Clark, J.R.
Quarterly Journal of Forestry - Quarterly Journal of Forestry 105, 39 2011
Ash in a changing climate
Clark, J.R
Woodland Heritage Journal - Woodland Heritage Journal 2012, 78-792012
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