Climate change and damage to trees caused by extremes of temperature

 

Climate change: Impacts on UK forests - Chapter 3
By Derek Redfern and Steven Hendry

Key findings

• The likelihood of injury to trees by winter cold may be slightly lower than at present. 
• It is likely that spring flushing will advance as a result of milder winters, but the risk of spring frost injury is unlikely to change; nevertheless, unseasonal frosts will still have the potential to cause damage. • Autumn frosts may become more damaging in England because of later hardening and predicted increases in diurnal temperature range in the south. 
• The widespread planting of southern provenances of species such as Sitka spruce, in anticipation of climate change, should be avoided because of the potential for unseasonal frost damage. 
• No prediction is possible for the frequency of the type of winter injury known as ‘red belt’. 
• ‘Top-dying’ of Norway spruce is likely to increase in England and eastern Scotland; Norway spruce could cease to be a productive species over much of England. 
• Increasing heat and drought in the south and east can be expected to increase losses, particularly among newly established trees and mature trees in hedgerows and urban environments. Defects in coniferous timber due to drought crack are also likely to increase in England. 
• An increased incidence of summer drought would make trees more vulnerable to attack by weak pathogens. 
• Increased winter rainfall may raise water tables enough to kill roots, thereby reducing effective rooting depth and making trees more vulnerable to summer droughts. 
• Higher temperatures in summer may reduce the risk of Brunchorstia damage to Corsican pine, enabling it to be planted more widely in the uplands in the future.

Next: Chapter 4 - Climate change impacts: storms

Previous: Chapter 2 - The changing climate of the UK: now and in the future