Managing a woodland with acute oak decline: Bell Coppice
This case study discusses the management of Bell Coppice, a woodland primarily composed of 120-year-old sessile oak (Quercus petraea), affected by acute oak decline (AOD). AOD was first identified in 2008 through characteristic bleeding patches on oak stems and confirmed by molecular diagnostics. The presence of the native beetle Agrilus biguttatus, associated with AOD, was also documented. The woodland management aims to balance commercial and conservation needs by maintaining oak as the main crop, enhancing habitat diversity through widened rides with scalloped edges, and using low-impact continuous cover timber extraction.
Climate change poses risks such as increased pest activity, drought stress, and more extreme weather events, potentially boosting insect damage and disease impact. Although it’s unclear whether AOD has become more frequent due to climate change, climatic factors are considered contributory. The vulnerability of the woodland includes environmental stressors like drought, poor soil, pest damage, and management practices which may influence AOD spread, often seen near south-facing ride edges favoring sun-warmed oak stems.
Management strategies focus on increasing tree species diversity, adjusting age structure, and reducing stand density to improve resilience. Proactive actions included felled affected trees to prevent disease spread and to harvest value, planting a varied mix of broadleaf species—oak, lime, hornbeam, cherry, hazel, and natural regeneration of silver birch—to diversify and spread future risks. Open areas were protected with deer fencing to promote natural oak regeneration, and species suited for future climates were introduced. The aim is to develop a more resilient woodland structure capable of withstanding pests, diseases, and climate stresses.
Monitoring has shown a decrease in symptomatic trees and less frequent AOD symptoms, possibly due to favorable climatic conditions boosting oak vigor. Thinning and selective harvesting (shelterwood approach) helped maintain a healthy, open canopy, supporting regeneration and reducing competition. Young oaks, less susceptible to AOD, are protected from bramble, bracken, and squirrel bark stripping to ensure successful establishment.
Lessons from this management include the importance of sanitation felling, expert advice, and adaptive approaches that reduce disease incidence and enhance resilience. Future objectives aim to foster a mixed age and species structure, increasing the woodland’s overall robustness against pests, diseases, and climate impacts. This approach exemplifies proactive, adaptive woodland management in response to disease outbreaks and climate change challenges, supporting both conservation and sustainable timber production.
[https://cdn.forestresearch.gov.uk/2022/05/UKFSPG026_CS2_Bell-Coppice.pdf Managing a woodland with acute
oak decline: Bell Coppice] (en)
Number of pages: 3
Target countries: United Kingdom
Key takeaways
- Proactive management, including sanitation felling, may reduce the incidence of acute oak decline (AOD).
- Felling affected trees before they die helps decrease cross-infection, improves resilience, and allows economic use of timber while supporting woodland health.
- Diversification of species and age structure enhances forest resilience to pests, diseases, and climate change impacts.
- Planting a mix of broadleaf species and regulating stand structure allows the woodland to better withstand AOD, climatic stresses, and potential future pests.
- Climate change influences forest pest dynamics by increasing insect reproductive rates, altering life cycles, and expanding geographical distribution.
- Warmer temperatures and altered weather patterns are likely to escalate damage from pests like aphids and bark beetles, necessitating adaptive management strategies.
- Increasing stand openness and encouraging regeneration can help reduce AOD symptoms and improve long-term forest health.
- Selective harvesting to create more open canopies and planting diverse species supports good regeneration and reduces susceptibility to pests and disease.
- Monitoring and early intervention are critical as AOD symptoms can show a trend of remission influenced by climatic conditions.
- Decreased AOD symptoms might be linked to favourable climatic conditions, emphasizing the importance of continuous health assessment and adaptive responses.
- Including a variety of tree species in new plantings may reduce future vulnerability to pests and climate impacts.
- Mixed-species planting, including oak, lime, cherry, and hazel, helps spread risks and create a more resilient woodland ecosystem.
Sources
- Managing a woodland with acute
oak decline: Bell Coppice - - https://cdn.forestresearch.gov.uk/2022/05/UKFSPG026_CS2_Bell-Coppice.pdf
