2.1 Evaluating climate-matching, impacts and exposure to pests and diseases
Using growth trials of climate matched tree species and provenances we are evaluating the variation in the severity of powdery mildew infections in conjunction with abundance and community composition of bacterial and fungal leaf endophytes and insect herbivores (i.a. gall wasps and leaf miners) found on oak trees.
These pests and diseases will be used as ‘model’ species to enable us to understand more generally how provenance and stand diversity affects oak susceptibility to pests and diseases.
More details about the Climate Match Trials can be found here.
2.2 Producing pest and disease related stress maps and horizon scanning
We are analysing the site characteristics of oak woodlands used in Work Package One to understand their association with the vigour of oak trees and whether they might indicate growing conditions where tree are not stressed. We are testing these associations at oak sites throughout Britain. By adjusting the climate variables used in this analysis to reflect the projected future climate, we will predict and map areas where we expect oak to become stressed and at risk of decline.
Knowledge about the potential of oak tree pests and diseases (including those already in the UK), provided by international experts, will be used by a national panel to assess risks to oak woodlands in Britain.
We are also identifying the tree species that may provide a suitable replacement to oak trees in areas of the UK where the health of oak woodlands is at high risk of stress leading to pest and disease impact. Species will be drawn from the emerging tree species list being evaluated by Forest Research.
2.3 Synthesising knowledge on oak ecosystem vulnerability, risks to silviculture and adaptive management pathways
In this part of our work we are considering the planning and practices required to help oak woodlands cope with threats. Scientific experts in silviculture (the cultivation of trees) will consider the strategies and actions that may be used to reduce the impact of a range of potential oak woodland pest and diseases including those identified in Objective 2.2
They will assess a range of forest management actions that may be used to reduce the levels of stress experienced by oak trees and to help control potential pests and diseases of oak trees. In situations where it is unlikely that the levels of stress can be reduced, different levels of woodland management sanitation practice, such as the felling and removal of trees, and their consequences, will be reviewed.
Using the information produced by this research, a novel approach using expert stakeholders will identify ‘adaptive management pathways’ to guide the selection and application of adaptation actions towards those which have least negative impacts on biodiversity and ecosystem services such as carbon storage and water quality.