Context

Oak is a crucial broadleaved tree species for biodiversity and hardwood timber. However, oak can be affected by a condition known as shake, which causes stem cracking and reduces the value and long-term use of harvested timber. There are several biological factors and environmental triggers known to contribute to shake, but the exact causes are not yet fully understood.

As the UK undertakes widespread woodland creation, oak is one of the most commonly planted species. This makes shake a critical economic risk for new oak woodlands intended for timber production and carbon net zero goals.

Research aims and objectives

Aim:

Improve understanding of the drivers behind oak shake, by studying known biological factors and environmental triggers, and linking the presence of shake with external indicators, such as stem form (the way that the trunk of a tree grows), acute oak decline, and the timing of bud-burst.

Objectives:

• Develop a non-destructive testing methodology to detect oak shake within standing trees using:
  • sonic tomography (a non-destructive testing technique that assesses the internal condition of trees by analysing how sound waves travel through the wood)
  • resistance microdrilling, which measures wood resistance using a fine drill needle to detect internal defects.
• Undertake shake assessments on standing oak trees that have had their full genetic makeup studied, using the non-destructive testing methodology, and identify possible genetic and environmental factors linked to shake.

Expected outcomes

• An improved understanding of what makes oak trees more likely to develop shake, what environmental conditions trigger it, and how these factors work together.
• Non-destructive testing methodology developed to detect shake in standing trees.
• Enhanced understanding of the genetic traits that make oak trees more likely to develop shake.